Stakeholder Meeting Review: ATXI True-Up Calculations 2015

2015 Attachment O True-Up Stakeholder Meeting Ameren Transmission Company of Illinois July 19, 2016

AGENDA Main Purpose is to review ATXI 2015 Transmission Rate True-Up Calculations Protocol Timeline 2015 True Up Calculation Total Revenue Requirement Comparison Projected vs Actual Attachment O/Schedule 9 True-up Attachment MM Revenue Requirement and True-up 2015 MVP Spend ROE Complaint Cases An additional meeting will held to review the 2017 Projected Transmission Rate calculations. Tentatively set for October 3rd. 2

PROTOCOL TIMELINE Schedule Date (Forward-Looking Protocols) June 1 Posting of annual true-up for prior year September 1 September 1 October 15 November 1 March 15 Deadline for annual true-up meeting Posting of net projected revenue requirement for following year Deadline for annual projected rate meeting Deadline for joint meeting on regional cost-shared projects Transmission Owners submit informational filing to the Commission 3

ATXI Revenue Requirement Comparison Projected 2015 vs Actual 2015 4

ATXI 2015 RATE BASE Page.Line 2015 Projection 2015 Actual Change Percent 2.6 Total Gross Plant 80,778,000 87,757,036 6,979,036 9% 2.12 Total Accum Depreciation 4,717,000 5,373,349 656,349 14% 2.18 TOTAL NET PLANT 76,061,000 82,383,687 6,322,687 8% 2.18a 100% CWIP RECOVERY 471,564,000 462,818,690 -8,745,310 -2% ADJUSTMENTS TO RATE BASE 2.20 Account No. 282 -12,824,000 -24,006,415 -11,182,415 87% 2.21 Account No. 283 -2,720,000 -3,545,081 -825,081 30% 2.22 Account No. 190 2,470,000 3,990,057 1,520,057 62% 2.25 Land Held for Future Use 0 0 0 N/A 2.26 CWC 866,625 1,386,288 519,663 60% 2.27 Materials & Supplies 0 0 0 N/A 2.28 Prepayments 190,000 375,152 185,152 97% TOTAL ADJUSTMENTS -12,017,375 -21,799,998 -9,782,623 81% 2.30 TOTAL RATE BASE 535,607,625 523,402,380 -12,205,245 -2% 5

ATXI 2015 EXPENSES Page.Line 2015 Projection 2015 Actual Change Percent O&M 3.1 Transmission 367,000 1,700,440 1,333,440 363% 3.1a Less LSE Expenses 0 0 0 N/A 3.2 Less Account 565 0 0 0 N/A 3.3 A&G 6,566,000 9,389,861 2,823,861 43% 3.4 Less FERC Annual Fees 0 0 0 N/A 3.5 Less EPRI, ect. 50,000 185,211 135,211 270% 3.5a Plus Trans. Reg. Comm. Exp 50,000 185,211 135,211 270% 3.8 TOTAL O&M 6,933,000 11,090,301 4,157,301 60% 3.12 TOTAL DEPRECIATION 1,132,000 1,921,460 789,460 70% TAXES 3.13 Payroll 0 0 0 N/A 3.16 Property 0 82,401 82,401 N/A 3.18 Other 155,000 204,132 49,132 32% 3.27 Income Taxes 24,806,313 24,229,707 -576,605 -2% TOTAL TAXES 24,961,313 24,516,240 -445,072 -2% TOTAL EXPENSES 33,026,313 37,528,002 4,501,689 14% 6

ATXI 2015 CAPITAL STRUCTURE Actual Capital Structure - 2015 Projection Page.Line 4.27 4.28 4.29 4.3 $ % Cost Weighted Long Term Debt Preferred Stock Common Stock 192,308,000 44% 0% 56% 100% 4.2700% 1.8700% 0.0000% 0.0000% 12.3800% 6.9600% 0 247,121,000 439,429,000 Total 8.8300% Actual Capital Structure - 2015 Actual Page.Line 4.27 4.28 4.29 4.3 $ % Cost Weighted Long Term Debt Preferred Stock Common Stock 182,307,692 44% 0% 56% 100% 3.1010% 1.3639% 0.0000% 0.0000% 12.3800% 6.9351% 0 232,202,030 414,509,722 Total 8.2989% Change in Actual Return -0.5311% Hypothetical Capital Structure - 2015 Actual Actual Capital Structure Return Hypothetical Capital Structure Return Difference applied to Attachment MM 8.2989% 8.2972% -0.0017% 7

ATXI 2015 TOTAL REVENUE REQUIREMENT Page.Line 2015 Projection 2015 Actual Change Percent 2.30 TOTAL RATE BASE 535,607,625 523,402,380 -12,205,245 -2% 4.30 Rate of Return on ACS 8.83% 8.30% -0.53% -6% 3.28 Return from ACS 47,306,341 43,436,896 -3,869,445 -8% 2.30a 100% CWIP RECOVERY 471,564,000 462,818,690 -8,745,310 -2% 4.30e Incremental Rate of Return on HCS -0.02% 0.00% 0.02% -91% 3.28a Incremental Return from HCS -90,541 -7,935 82,606 -91% Total Return 47,215,800 43,428,961 -3,786,839 -8% Total Expenses 33,026,313 37,528,002 4,501,689 14% 3.29 TOTAL GROSS REV. REQ. 80,242,113 80,956,963 714,850 1% 3.30 Less ATT. GG Adjustment 0 0 0 N/A 3.30a Less ATT. MM Adjustment 71,386,314 71,231,892 -154,422 0% 3.31 GROSS REV. REQ. UNDER ATT. O 8,855,799 9,725,070 869,272 10% 8

ATXI 2015 NET REVENUE REQUIREMENT FOR SCHEDULE 9 Page.Line 2015 Projection 2015 Actual Change Percent 1.1 Gross Revenue Requirement 8,855,799 9,725,070 869,272 10% 1.6 Total Revenue Credits 423,000 1,100,154 677,154 160% 1.6a Historic Year Actual ATRR* 8,860,739 8,860,739 0 0% 1.6b Projected ATRR from Prior Year* 7,406,002 7,406,002 0 0% 1.6c Prior Year ATRR True-Up* 1,454,736 1,454,736 0 0% 1.6d Prior Year Divisor True-Up* (45,647) (45,647) 0 0% 1.6e Interest on Prior Year True-Up* 9,706 9,706 0 0% 1.7 NET REVENUE REQUIREMENT 9,851,594 10,043,711 192,118 2% * 2013 True-up included in 2015 Projection and Actual. 9

ATXI 2015 ATTACHMENT O TRUE UP FOR SCHEDULE 9 Ameren Transmission Company of Illinois 2015 Attachment O Revenue Requirement True-Up (WP 4) For the Year Ended December 31, 2015 Attachment O Net Actual Revenue Requirement (Attachment O, Pg 1, Line 7) Net Projected Revenue Requirement (2015 Projected Attachment O, Pg 1, Line 7) 10,043,711 9,851,594 Under/(Over) Recovery of Net Revenue Requirement $ 192,117 Historic Year Actual Divisor for Pricing Zone (AIC Attachment O, Pg 1, Line 15) Projected Year Divisor for Pricing Zone (AIC 2015 Projected Attachment O, Pg 1, Line 15) Difference between Historic & Projected Yr Divisor Prior Year Projected Annual Cost ($ per kw per yr) 6,922,407 7,095,335 172,928 1.3885 Prior Year Under/(Over) Divisor True-up $ 240,110 Total Under/(Over) Recovery $ 432,227 Monthly Interest Rate (to be updated through July, 2016) Interest For 24 Months 0.0311% $ 3,226 Total Under/(Over) Recovery Including Interest (Amount to be included in Projected 2017 Attachment O) $ 435,454 10

ATXI 2015 ATTACHMENT MM ATXI Attachment MM Calculation - Page 1 Attachment O Page, Line, Col. Line No. Transmission Allocator 1 1a 2 Gross Transmission Plant - Total Transmission Accumulated Depreciation Net Transmission Plant - Total Attach O, p 2, line 2 + 18a col 5 (Note A) Attach O, p 2, line 8 col 5 Line 1 minus Line 1a (Note B) 547,049,166 4,693,803 542,355,363 O&M TRANSMISSION EXPENSE Total O&M Allocated to Transmission Transmission O&M 3 3a Attach O, p 3, line 8 col 5 Attach O, p 3, line 1 col 5 11,090,301 1,700,440 3b Less: LSE Expenses included in above, if any Attach O, p 3, line 1a col 5, if any - 3c Less: Account 565 included in above, if any Attach O, p 3, line 2 col 5, if any - 3d Adjusted Transmission O&M Line 3a minus Line 3b minus Line 3c 1,700,440 4 Annual Allocation Factor for Transmission O&M (Line 3d divided by line 1a, col 3) 36.23% 36.23% OTHER O&M EXPENSE Other O&M Allocated to Transmission Annual Allocation Factor for Other O&M 4a 4b Line 3 minus Line 3d Line 4a divided by Line 1, col 3 9,389,861 1.72% 1.72% GENERAL AND COMMON (G&C) DEPRECIATION EXPENSE 5 6 Total G&C Depreciation Expense Annual Allocation Factor for G&C Depreciation Expense Attach O, p 3, lines 10 & 11, col 5 (Note H) (line 5 divided by line 1 col 3) 722,457 0.13% 0.13% TAXES OTHER THAN INCOME TAXES Total Other Taxes Annual Allocation Factor for Other Taxes 7 8 Attach O, p 3, line 20 col 5 (line 7 divided by line 1 col 3) 286,533 0.05% 0.05% 9 Annual Allocation Factor for Other Expense Sum of line 4b, 6, and 8 1.90% INCOME TAXES Total Income Taxes Annual Allocation Factor for Income Taxes 10 11 Attach O, p 3, line 27 col 5 (line 10 divided by line 2 col 3) 24,229,707 4.47% 4.47% RETURN Return on Rate Base (Note I) Annual Allocation Factor for Return on Rate Base 12 13 Attach O, p 3, line 28 col 5 (line 12 divided by line 2 col 3) 43,436,896 8.01% 8.01% 14 Annual Allocation Factor for Return Sum of line 11 and 13 12.48% HYPOTHETICAL CAPITAL STRUCTURE (HCS) RETURN Annual Allocation Factor HCS Return (Note J) 15 Attach O, p 4, line 30e 0.00% 0.00% 11

ATXI 2015 ATTACHMENT MM ATXI Attachment MM Calculation - Page 2 (1) (2) (3) (4) (5) (6) (7) (8) (9) Transmission O&M Annual Allocation Factor Other Expense Annual Allocation Factor MTEP Project Number Project Accumulated Depreciation Annual Allocation for Transmission O&M Expense Annual Allocation for Other Expense Annual Expense Charge Line No. Project Name Project Gross Plant (Note C) Page 1 line 4 (Col 4 * Col 5) Page 1 line 9 (Col 3 * Col 7) (Col 6 + Col 8) Multi-Value Projects (MVP) 1a Pana-Sugar Creek - CWIP 1b Pana-Sugar Creek - Plant in Service - No HCS 1c Pana-Sugar Creek - Land - No HCS 1d Sidney-Rising - CWIP 1e Sidney-Rising - Plant in Service - No HCS 1f Sidney-Rising - Land - No HCS 1g Adair-Ottumwa - CWIP 1h Adair-Ottumwa - Plant in Service - No HCS 1i Adair-Ottumwa - Land - No HCS 1j Palmyra-Pawnee - CWIP 1k Palmyra-Pawnee - Plant in Service - No HCS 1l Palmyra-Pawnee - Land - No HCS 1m Fargo-Galesburg-Oak Grove - CWIP 1n Fargo-Galesburg-Oak Grove - Plant in Service - No HCS 1o Fargo-Galesburg-Oak Grove - Land - No HCS 1p Pawnee-Pana - CWIP 1q Pawnee-Pana - Plant in Service - No HCS 1r Pawnee-Pana - Land - No HCS 1s Adair-Palmyra - CWIP 1t Adair-Palmyra - Plant in Service - No HCS 1u Adair-Palmyra - Land - No HCS 2237 2237 2237 2239 2239 2239 2248 2248 2248 3017 3017 3017 3022 3022 $ 90,099,171 $ - $ 7,478,744 $ 17,645 $ 4,246,528 $ - $ 47,931,651 $ - $ 2,106,101 $ 3,305 $ 1,285,913 $ - $ 1,052,148 $ - $ - $ - $ 655,929 $ - $ 257,736,281 $ - $ - $ - $ 8,170,113 $ - $ 10,606,966 $ - $ - $ - 36.23% $ - 36.23% $ 6,392 36.23% $ - 36.23% $ - 36.23% $ 1,197 36.23% $ - 36.23% $ - 36.23% $ - 36.23% $ - 36.23% $ - 36.23% $ - 36.23% $ - 36.23% $ - 36.23% $ - 1.90% $ 1,712,694 1.90% $ 142,163 1.90% $ 80,722 1.90% $ 911,132 1.90% $ 40,035 1.90% $ 24,444 1.90% $ 20,000 1.90% $ - 1.90% $ 12,469 1.90% $ 4,899,306 1.90% $ - 1.90% $ 155,306 1.90% $ 201,628 1.90% $ - $ 1,712,694 $ 148,556 $ 80,722 $ 911,132 $ 41,232 $ 24,444 $ 20,000 $ - $ 12,469 $ 4,899,306 $ - $ 155,306 $ 201,628 $ - 3022 3169 3169 $ 3,394,442 $ - $ 31,771,366 $ - $ - $ - 36.23% $ - 36.23% $ - 36.23% $ - 1.90% $ 64,525 1.90% $ 603,942 1.90% $ - $ 64,525 $ 603,942 $ - 3169 3170 3170 3170 $ 3,429,159 $ - $ 23,621,106 $ - $ - $ - $ 769,450 $ - 36.23% $ - 36.23% $ - 36.23% $ - 36.23% $ - 1.90% $ 65,185 1.90% $ 449,013 1.90% $ - 1.90% $ 14,626 $ 65,185 $ 449,013 $ - $ 14,626 12

ATXI 2015 ATTACHMENT MM ATXI Attachment MM Calculation - Page 2 (continued) (1) (2) (10) (11) (11a) (12) (13) (14) (15) (16) Annual Allocation Factor for Return Annual Allocation Factor for HCS Return MTEP Project Number Project Depreciation Expense MVP Annual Adjusted Revenue Requirement Annual Return Charge Annual Revenue Requirement Line No. Project Name Project Net Plant True-Up Adjustment (Page 1 line 15) (Note J) (Col 10 * (Col 11 + 11a)) Sum Col. 14 & 15 (Note G) (Col 3 - Col 4) (Page 1 line 14) (Note E) (Sum Col. 9, 12 & 13) (Note F) Multi-Value Projects (MVP) 1a 1b 1c 1d 1e 1f 1g 1h 1i 1j 1k 1l 1m 1n 1o 1p 1q 1r 1s 1t 1u Pana-Sugar Creek - CWIP Pana-Sugar Creek - Plant in Service - No HCS Pana-Sugar Creek - Land - No HCS Sidney-Rising - CWIP Sidney-Rising - Plant in Service - No HCS Sidney-Rising - Land - No HCS Adair-Ottumwa - CWIP Adair-Ottumwa - Plant in Service - No HCS Adair-Ottumwa - Land - No HCS Palmyra-Pawnee - CWIP Palmyra-Pawnee - Plant in Service - No HCS Palmyra-Pawnee - Land - No HCS Fargo-Galesburg-Oak Grove - CWIP Fargo-Galesburg-Oak Grove - Plant in Service - No HCS Fargo-Galesburg-Oak Grove - Land - No HCS Pawnee-Pana - CWIP Pawnee-Pana - Plant in Service - No HCS Pawnee-Pana - Land - No HCS Adair-Palmyra - CWIP Adair-Palmyra - Plant in Service - No HCS Adair-Palmyra - Land - No HCS 2237 2237 2237 2239 2239 2239 2248 2248 2248 3017 3017 3017 3022 3022 3022 3169 3169 3169 3170 3170 3170 $ 90,099,171 $ 7,461,099 $ 4,246,528 $ 47,931,651 $ 2,102,796 $ 1,285,913 $ 1,052,148 $ - $ 655,929 $ 257,736,281 $ - $ 8,170,113 $ 10,606,966 $ - $ 3,394,442 $ 31,771,366 $ - $ 3,429,159 $ 23,621,106 $ - $ 769,450 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 12.48% 0.00% $ 11,239,618 $ - $ 12,952,312 0.00% $ 930,879 $ 127,524 $ 1,206,959 0.00% $ 529,815 $ - $ 610,537 0.00% $ 5,979,339 $ - $ 6,890,471 0.00% $ 262,354 $ 32,259 $ 335,845 0.00% $ 160,436 $ - $ 184,880 0.00% $ 131,253 $ - $ 151,253 0.00% $ - $ - $ - 0.00% $ 81,837 $ - $ 94,305 0.00% $ 32,151,876 $ - $ 37,051,182 0.00% $ - $ - $ - 0.00% $ 1,019,339 $ - $ 1,174,644 0.00% $ 1,323,189 $ - $ 1,524,817 0.00% $ - $ - $ - 0.00% $ 423,505 $ - $ 488,030 0.00% $ 3,963,388 $ - $ 4,567,330 0.00% $ - $ - $ - 0.00% $ 427,837 $ - $ 493,022 0.00% $ 2,946,666 $ - $ 3,395,680 0.00% $ - $ - $ - 0.00% $ 96,000 $ - $ 110,626 $ (492,359) $ 12,459,953 $ 1,206,959 $ 821,839 $ 6,755,808 $ 335,845 $ 356,121 $ 211,302 $ (134,662) $ 171,241 $ - $ 151,253 $ - $ - $ 94,305 $ (404,306) $ 36,646,876 $ - $ 1,216,042 $ 2,390,687 $ 557 $ 1,525,374 $ - $ 44,343 $ 532,373 $ 59,313 $ 4,626,643 $ - $ 931,608 $ 3,683,281 $ - $ 229,841 $ 438,587 $ 287,601 $ 119,215 2 MVP Total Annual Revenue Requirements $71,231,892 $1,516,874 $72,748,766 3 Rev. Req. Adj For Attachment O $71,231,892 13

ATXI 2015 ATTACHMENT MM TRUE-UP FOR SCHEDULE 26-A (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) Actual Projected Annual Revenue Attachment MM Revenues Allocated Actual Annual Revenue True-Up Adjustment Principal Applicable Interest Rate on True-Up Adjustment Interest MTEP Project Actual Total True-Up Line Project Attachment MM No. Name Number Revenues Requirement 1 Projected Attachment MM to Projects 1 [Col. (d), line 1 x (Col. (e), line 2x / Requirement 1 Actual Attachment MM Under/(Over) Under/(Over) Under/(Over) Adjustment Col. (h) x Col. (i) p 2 of 2, Col. 142 Col. (e), line 3)]2 p 2 of 2, Col. 142 Col. (g) - Col. (f) Line 5 x 24 months 2 Col. (h) + Col. (j) 1 Actual Attachment MM revenues for True-Up Year 1 2a Pana-Sugar Creek - CWIP 2b Pana-Sugar Creek - Plant in Service - No HCS 2c Pana-Sugar Creek - Land - No HCS 2d Sidney-Rising - CWIP 2e Sidney-Rising - Plant in Service - No HCS 2f Sidney-Rising - Land - No HCS 2g Adair-Ottumwa - CWIP 2h Adair-Ottumwa - Plant in Service - No HCS 2i Adair-Ottumwa - Land - No HCS 2j Palmyra-Pawnee - CWIP 2k Palmyra-Pawnee - Plant in Service - No HCS 2l Palmyra-Pawnee - Land - No HCS 2m Fargo-Galesburg-Oak Grove - CWIP 2n Fargo-Galesburg-Oak Grove - Plant in Service - No HCS 2o Fargo-Galesburg-Oak Grove - Land - No HCS 2p Pawnee-Pana - CWIP 2q Pawnee-Pana - Plant in Service - No HCS 2r Pawnee-Pana - Land - No HCS 2s Adair-Palmyra - CWIP 2t Adair-Palmyra - Plant in Service - No HCS 2u Adair-Palmyra - Land - No HCS 66,274,859 2237 2237 2237 2239 2239 2239 2248 2248 2248 3017 3017 3017 3022 3022 3022 3169 3169 3169 3170 3170 3170 15,120,908 778,416 405,274 7,297,352 14,038,210 722,679 376,255 6,774,842 12,952,312 1,206,959 610,537 6,890,471 335,845 184,880 151,253 (1,085,898) 484,280 234,282 115,629 335,845 14,306 (49,288) 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% 0.03% (8,105) 3,615 1,749 863 2,507 107 (368) (1,094,003) 487,895 236,031 116,492 338,352 14,413 (49,656) - - 183,729 216,008 170,574 200,541 - - - - - 48 - 94,653 87,876 94,305 6,429 6,477 35,301,697 32,773,999 37,051,182 4,277,183 31,925 4,309,108 - - - - - - 1,176,298 2,061,101 1,092,072 1,913,521 1,174,644 1,524,817 82,572 (388,704) 616 83,188 (391,605) (2,901) - - - - - - 488,283 4,009,140 453,321 3,722,075 488,030 4,567,330 34,709 845,255 259 34,968 851,564 6,309 - - - - - - 404,762 3,738,008 375,780 3,470,356 493,022 3,395,680 117,242 (74,676) 875 (557) 118,117 (75,233) - - - - - 59 - 110,686 102,761 110,626 7,865 7,924 3 Subtotal $ 71,386,315 $ 66,274,862 $ 71,231,893 4 Under/(Over) Recovery $ 4,957,031 $ 37,001 $ 4,994,032 5 Applicable Interest rate per month (expressed to four decimal places) interest rate to be updated through July 31, 2016 0.0311% 1 Amount excludes True-Up Adjustment, as reported in True-Up Year projected Attachment MM, page 2, column 15. 2 Rounded to whole dollars. 14

ATXI 2015 MVP SPEND Ameren MVPs Ameren Name 2015 CAPEX MTEP #s MTEP Description 2237 2239 3017 3169 3170 Pana - Mt. Zion - Kansas - Sugar Creek 345 kV line Sidney to Rising 345 kV line Palmyra-Quincy-Meredosia - Ipava & Meredosia-Pawnee 345 kV Line Pawnee to Pana - 345 kV Line New Palmyra Substation (Maywood) Illinois Rivers $354 million Spoon River $23 million 3022 Fargo-Galesburg-Oak Grove 345 kV Line 2248 3170 Adair - Ottumwa 345 Adair-Palmyra 345 kV Line Mark Twain $2 million 15

ROE COMPLAINTS Current ROE is 12.38% MISO ROE Complaints 1st Complaint (EL14-12) Covers November 12, 2013 through Feb 11, 2015 Received initial decision from administrative law judge on December 22, 2015 with a recommended Base ROE at 10.32% Expect final FERC order in October 2016 2nd Complaint (EL15-45) Covers February 12, 2015 through May 11, 2016 Received initial decision on June 30, 2016 with a recommended Base ROE at 9.70% Expect final FERC order in first half of 2017 16

ROE COMPLAINTS FERC approved a 50 basis point adder for participation in an RTO Effective January 6, 2015, but will not be used until after final orders in the ROE complaints are issued Refunds will be required, but format is not yet determined Will impact Schedules 7,8, 9, 26, 37, 38, 26A Amounts could be either be rolled into the future revenue requirements and reduce future rates actual refunds to all customers requiring MISO to calculate adjustments for all months beginning with November 13 17

QUESTIONS?

Appendix Supplemental Background Information (Not covered during presentation) 19

APPENDIX - MISO ATTACHMENTS O & MM Calculate rates for Schedules 9, 26 & 26-A Attachment GG - Schedule 26 Attachment MM - Schedule 26-A Attachment O - net revenue requirement billed under Schedule 9 Schedules 26 and 26-A are billed by MISO Schedule 9 is billed by Ameren 20

APPENDIX - MISO ATTACHMENT MM Cost recovery for Multi-Value Projects (MVPs) Criteria for being considered Developed through planning process and support energy policy Multiple types of economic value across multiple pricing zones with benefit to costs > 1 Address at least one: Projected NERC violation Economic-based issue Cost shared across MISO based on load AMIL Zone is approximately 10% Ameren MVPs will primarily be built by ATXI AIC will be responsible for modifications needed to its existing facilities 21

APPENDIX - MISO ATTACHMENT O & MM All transmission costs included in Attachment O calculation Schedule 9 based on net revenue requirement reductions for: Costs recovered in Schedules 26 & 26-A Since ATXI has no Attachment GG projects, there is no deduction for 26 Revenue Credits Point-to-Point revenue in Schedules 7 & 8 Rental revenue Revenue from generator interconnections 22

APPENDIX - MISO TRANSMISSION EXPANSION PLAN (MTEP) Developed on an annual basis building upon previous analysis MISO, Transmission Owners & Stakeholders Includes subregional planning meetings MTEP goals Ensure the reliability of the transmission system Ensure compliance with NERC Standards Provide economic benefits, such as increased market efficiency Facilitate public policy objectives, such as meeting Renewable Portfolio Standards Address other issues or goals identified through the stakeholder process Multiple future scenarios analyzed End result comprehensive, cohesive plan for MISO footprint MTEP approved by MISO Board of Directors 23

MISO MVPS Brief history of development Began investigating value added expansion in 2003 2008 Regional Generation Outlet Study (RGOS) - formed basis of Candidate MVP portfolio Portfolio refined due to additional analysis MISO approved portfolio of 17 Projects Seven transmission line segments (MTEP proj numbers) in Ameren territory Ameren identifies these three projects as: Illinois Rivers (four line segments) Spoon River Mark Twain (two line segments) Broadly cost-shared, AMIL pricing zone allocated 10% of each MVP no matter where project is located or who builds it 24

APPENDIX - MAP OF AMEREN MVPS 25

APPENDIX - RATE INCENTIVES FERC approved the following rate incentives for Illinois Rivers in Docket No. EL10-80 CWIP (no AFUDC) Abandonment (requires additional filing prior to recovery) Hypothetical capital structure during construction for ATXI FERC approved similar incentives for Spoon River and Mark Twain Projects in Docket No. ER12-2216 26

APPENDIX - MISO WEB LINKS Transmission Pricing - Attachments O, GG & MM Information https://www.misoenergy.org/MarketsOperations/TransmissionSettlement s/Pages/TransmissionPricing.aspx Ameren OASIS http://www.oasis.oati.com/AMRN/index.html MTEP 15 https://www.misoenergy.org/Planning/TransmissionExpansionPlanning/ Pages/MTEP15.aspx MTEP 16 https://www.misoenergy.org/Planning/TransmissionExpansionPlanning/ Pages/MTEP16.aspx Schedule 26 & 26-A Indicative Charges https://www.misoenergy.org/Planning/TransmissionExpansionPlanning/ Pages/MTEPStudies.aspx 27

APPENDIX - ATXI Additional questions on these topics can be sent to Ameren at: MISOFormulaRates@ameren.com 28