2016 Attachment O True-Up Stakeholder Meeting Ameren Transmission Company of Illinois July 27, 2017

Purpose is to review ATXI 2016 Transmission Rate True-Up Calculations Agenda Purpose is to review ATXI 2016 Transmission Rate True-Up Calculations Protocol Timeline ROE Complaint Cases and Impact on True-up calculations 2016 True Up Calculation Total Revenue Requirement Comparison – Projected vs Actual Summary of Revenue Requirements at 12.38% and 10.82% ROE Attachment O/Schedule 9 Weighted True-up Attachment MM/Schedule 26-A Weighted True-up 2016 MVP Spend 2016 Significant Projects Placed In Service An separate meeting will held to review the 2018 Projected Transmission Rate calculations. Tentatively set for September 21, 2017.

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

ROE complaints MISO ROE Complaints RTO Adder (ER15-358) 1st Complaint (EL14-12) Covers November 12, 2013 through February 11, 2015 FERC order received September 28, 2016; set the Base ROE at 10.32% Applicable going forward until 2nd complaint order 2nd Complaint (EL15-45) Covers February 12, 2015 through May 11, 2016 Initial decision issued June 30, 2016; recommended Base ROE at 9.70% Additional refunds will be required upon receipt of Final Order RTO Adder (ER15-358) FERC approved a 50 basis point adder for participation in an RTO Effective January 6, 2015, applicable to complaint case refunds after that date and going forward (i.e., total ROE is now 10.82%)

MISO ROEs for the 2016 True-Up ROE complaints MISO ROEs for the 2016 True-Up 12.38% ROE for January 1 – September 27 10.82% ROE for September 28 – December 31 Refunds already provided for EL14-12 Two phase process Phase 1 related to ROE impact on projected rates for forward looking TOs and annual updates for historical TOs. These were settled in February 2017. 2013, 2014 & 2015 projected rates from 11/12/13 to 2/11/15 Phase 2 related to the ROE impact on true-ups calculations for forward looking TOs. These were settled in June 2017. 2013, 2014 & 2015 True-ups included in 2015, 2016 and 2017 projected rates Refunds for Schedules 7, 8, 26, 37, 38, 26A were completed by MISO Refunds for Schedule 9 were processed by Ameren Schedule 9 Refund amounts and supporting documents are posted on Ameren’s OASIS

ATXI 2016 ROE Weightings Schedule 9 has been weighted based on the actual 2016 Load in the AMIL pricing zone Schedule 26-A has been weighted on the monthly percentage of applicable withdrawals from the prior year consistent with the monthly allocation of the total MVP revenue requirement September load and revenue split based on number of days (i.e., 27 days at 12.38% and 3 days at 10.82%)

ATXI Revenue Requirement Comparison Projected 2016 vs Actual 2016 (Complete 2016 True-up calculations with ROE at 12.38 % and 10.32% are included in the posted file.)

Atxi 2016 Rate Base Page.Line 2016 Proj 2016 Act Change Percent 2.6 Total Gross Plant 244,237,971 262,579,385 18,341,414 8% 2.12 Total Accum Depreciation 9,096,778 8,301,568 (795,211) -9% 2.18 TOTAL NET PLANT 235,141,193 254,277,817 19,136,625 2.18a 100% CWIP RECOVERY 684,234,021 690,164,995 5,930,974 1% ADJUSTMENTS TO RATE BASE 2.20 Account No. 282 (39,044,786) (89,023,692) (49,978,906) 128% 2.21 Account No. 283 (3,708,928) (2,415,951) 1,292,977 -35% 2.22 Account No. 190 28,380,390 31,112,986 2,732,596 10% 2.25 Land Held for Future Use - N/A 2.26 CWC 1,575,005 1,386,593 (188,411) -12% 2.27 Materials & Supplies 2.28 Prepayments 392,795 377,426 (15,369) -4% TOTAL ADJUSTMENTS (12,405,525) (58,562,638) (46,157,113) 372% 2.30 TOTAL RATE BASE 906,969,689 885,880,175 (21,089,514) -2%

ATXI 2016 Expenses Page.Line 2016 Proj 2016 Act Change Percent O&M 3.1 Transmission 1,200,387 2,861,811 1,661,424 138% 3.1a Less LSE Expenses - N/A 3.2 Less Account 565 3.3 A&G 11,399,650 8,230,935 (3,168,715) -28% 3.4 Less FERC Annual Fees 3.5 Less EPRI, ect. 51,164 26,233 (24,931) -49% 3.5a Plus Trans. Reg. Comm. Exp 3.8 TOTAL O&M 12,600,037 11,092,746 (1,507,291) -12% 3.12 TOTAL DEPRECIATION 5,736,352 5,386,753 (349,599) -6% TAXES 3.13 Payroll 3.16 Property 763,426 681,375 (82,051) -11% 3.18 Other 500,000 516,357 16,357 3% 3.27 Income Taxes @10.82% ROE 36,714,667 35,771,390 (943,276) -3% TOTAL TAXES 37,978,093 36,969,122 (1,008,970) TOTAL EXPENSES 56,314,482 53,448,621 (2,865,860) -5% Income Taxes based on 12.38% ROE were $42,008,093 for projected and $40,928,818 for actuals resulting in Total Expenses of $61,607,909 for projected and $ 58,606,049 for actuals.

Atxi 2016 capital structure   12.38% ROE Actual Capital Structure - 2016 Projection Hypothetical Capital Structure - 2016 Projection Page.Line $ % Cost Weighted Actual Capital Structure Return 8.6638% 4.27 Long Term Debt 303,846,154 44% 3.9095% 1.7152% Hypothetical Capital Structure Return 8.6530% 4.28 Preferred Stock 0% 0.0000% Difference applied to Attachment MM -0.0109% 4.29 Common Stock 388,732,961 56% 12.3800% 6.9487% 4.3 Total 692,579,115 100% Actual Capital Structure - 2016 Actual Hypothetical Capital Structure - 2016 Actual 8.3565% 326,923,077 3.1866% 1.3946% 8.3349% -0.0216% 420,079,280 6.9619% 747,002,357 Change in Actual Return -0.3073% Change in Hypothetical Return -0.3181% 10.82% ROE 7.7882% 7.7794% -0.0089% 10.8200% 6.0731% 7.4793% 7.4613% -0.0180% 6.0847% -0.3090%

ATXI 2016 total revenue requirement 12.38% ROE Page.Line Projected Actual Change Percent 2.30 TOTAL RATE BASE 906,969,689 885,880,175 (21,089,514) -2% 4.30 Rate of Return on ACS 8.66% 8.36% -0.31% -4% 3.28 Return from ACS 78,578,452 74,028,860 (4,549,592) -6% 2.30a 100% CWIP RECOVERY 684,234,021 690,164,995 5,930,974 1% 4.30e Incremental Rate of Return on HCS -0.01% -0.02% 99% 3.28a Incremental Return from HCS (74,367) (149,320) (74,953) 101% Total Return 78,504,085 73,879,540 (4,624,545) Total Expenses 61,607,909 58,606,049 (3,001,860) -5% 3.29 TOTAL GROSS REV. REQ. 140,111,994 132,485,590 (7,626,404) 3.30 Less ATT. GG Adjustment - N/A 3.30a Less ATT. MM Adjustment 130,383,256 122,311,970 (8,071,286) 3.31 GROSS REV. REQ. UNDER ATT. O 9,728,737 10,173,620 444,882 5% 10.82% ROE 7.79% 7.48% 70,637,010 66,257,288 (4,379,722) 103% (60,671) (123,982) (63,311) 104% 70,576,339 66,133,306 (4,443,033) 56,314,482 53,448,621 (2,865,860) 126,890,821 119,581,927 (7,308,894) 117,855,536 110,071,470 (7,784,066) -7% 9,035,285 9,510,458 475,172

Atxi 2016 Net Revenue Requirement For Schedule 9 12.38% ROE Page.Line Projected Actual Change Percent 1.1 Gross Revenue Requirement 9,728,737 10,173,620 444,882 5% 1.6 Total Revenue Credits 990,564 908,498 (82,066) -8% 1.6a Historic Year Actual ATRR 10,018,898 - 0% 1.6b Projected ATRR from Prior Year 9,793,999 1.6c Prior Year ATRR True-Up 224,899 1.6d Prior Year Divisor True-Up (222,920) 1.6e Interest on Prior Year True-Up 31,082 1.7 NET REVENUE REQUIREMENT 8,771,234 9,298,182 526,948 6% 10.82% ROE 9,035,285 9,510,458 475,172 8,077,782 8,635,020 557,239 7% Prior year true-ups shown above represent the 2014 revised true-up at 10.32% ROE as a result of the Order in Docket EL14-12. The 2014 true –up at 12.38% ROE was originally included in 2016 rates.

Attachment O & MM Revenue Requirement Summary 12.38% ROE Projected Actual Change Percent Total Revenue Requirement 140,111,994 132,485,590 -7,626,404 -5.4% Less Attachment MM Rev Req 130,383,256 122,311,970 -8,071,286 -6.2% Gross Attachment O Rev Req 9,728,737 10,173,620 444,882 4.6% Less Revenue Credits 990,564 908,498 -82,066 -8.3% Plus Total Prior Year True-up 33,061 0.0% Net Attachment O Rev Req 8,771,234 9,298,182 526,948 6.0% 10.82% ROE 126,890,821 119,581,927 -7,308,894 -5.8% 117,855,536 110,071,470 -7,784,066 -6.6% 9,035,285 9,510,458 475,172 5.3% 8,077,782 8,635,020 557,239 6.9% Shaded cells used in True-up calculations   Prior year true-ups shown above represent the 2014 revised true-up at 10.32% ROE as a result of the Order in Docket EL14-12. The 2014 true –up at 12.38% ROE was originally included in 2016 rates.

ATXI 2016 attachment o true up for Schedule 9 Attachment O 2016 True-up calculation (Schedule 9)   2016 Rev Req at 2016 Weighted Calculation of 2016 Weighted Attachment O Rev Req 12.38% 10.82% Rev Req Net Actual 2016 Rev Req (Actual Attach O, Pg 1, Line 7) $9,298,182 $8,635,020 Percent of Actual Revenue Requirement at ROE 76.48% 23.52% Weighted Net Actual 2016 Rev Requirement $7,111,250 $2,030,957 $9,142,207 Net Projected 2016 Rev Req (Projected Attach O, Pg 1, Line 7)1 $8,771,234 $8,077,782 Percent of Projected Revenue at ROE Weighted Net Projected 2016 Rev Requirement $6,708,240 $1,899,894 $8,608,134 Under/(Over) Collection of 2016 Weighted Net Rev Req 403,010 131,063 534,073 Historic Year Actual Divisor for Transmission Owner (AIC Attach O, Pg 1, Line 15) 6,995,394 Proj'd Yr Divisor for Transmission Owner (AIC Projected Attach O, Pg 1, Line 15) 7,118,197 Difference between Historic & Projected Yr Divisor 122,804 Prior Year Projected Annual Cost ($ per kw per yr) $1.2322 $1.1348 Percent of Revenue Received at ROE Weighted Prior Yr projected Annual Cost ($ per kw per year) $0.9424 $0.2669 $1.2093 Under/(Over) Collection of 2016 Divisor True-up $148,507 Total Under/(Over) Recovery 682,580 Monthly Interest Rate (Over collection = FERC rate, Under collection = company rate) 0.0561% Interest For 24 Months $9,190 Total 2016 Attachment O True-up Under/(Over) Recovery (To be included in Projected 2018) $ 691,770

ATXI 2016 attachment MM true-up for Schedule 26-A

ATXI 2016 attachment MM true-up for Schedule 26-A ATXI 2016 Weighted Attachment MM True Up by Project 2016 Attachment MM True-Up Adjustment - Weighted   To be completed after the Attachment MM using actual data is completed for the True-Up Year Company Name: ATXI True-Up Year: 2016 (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) Actual Projected Attachment MM True-Up Applicable MTEP Annual Revenues Adjustment Interest Total Line Project Revenue Allocated Principal Rate on No. Name Number Requirement 1 to Projects 1 Under/(Over) [Col. (d), line 1 x (Col. (e), line 2x / Col. (h) x Col. (i) p 2 of 2, Col. 142 Col. (e), line 3)]2 Col. (g) - Col. (f) Line 5 x 24 months 2 Col. (h) + Col. (j) 1 Actual Attachment MM revenues for True-Up Year 1 $ 118,545,497 1a Pana-Sugar Creek - CWIP 2237 $ 18,739,217 $ 17,421,338 $ 15,031,901 $ (2,389,437) 0.056% $ (32,171) $ (2,421,608) 1b Pana-Sugar Creek - Plant in Service - No HCS $ 6,598,547 $ 6,134,489 $ 8,284,965 $ 2,150,476 $ 28,954 $ 2,179,430 1c Pana-Sugar Creek - Land - No HCS $ 647,187 $ 601,672 $ 585,097 $ (16,575) $ (223) $ (16,798) 1d Sidney-Rising - CWIP 2239 $ 7,357,601 $ 6,840,161 $ 5,320,101 $ (1,520,060) $ (20,466) $ (1,540,526) 1e Sidney-Rising - Plant in Service - No HCS $ 3,765,799 $ 3,500,960 $ 5,063,211 $ 1,562,251 $ 21,034 $ 1,583,285 1f Sidney-Rising - Land - No HCS $ 183,954 $ 171,017 $ 167,243 $ (3,774) $ (51) $ (3,825) 1g Adair-Ottumwa - CWIP 2248 $ 607,000 $ 564,311 $ 414,322 $ (149,989) $ (2,019) $ (152,008) 1h Adair-Ottumwa - Plant in Service - No HCS $ - $ - $ - $ - 1i Adair-Ottumwa - Land - No HCS $ 93,865 $ 87,264 $ 85,344 $ (1,920) $ (26) $ (1,946) 1j Palmyra-Pawnee - CWIP 3017 $ 52,940,322 $ 49,217,171 $ 53,842,364 $ 4,625,193 $ 62,274 $ 4,687,467 1k Palmyra-Pawnee - Plant in Service - No HCS $ 14,363,412 $ 13,353,272 $ 9,881,934 $ (3,471,338) $ (46,738) $ (3,518,076) 1l Palmyra-Pawnee - Land - No HCS $ 1,168,662 $ 1,086,473 $ 1,144,888 $ 58,415 $ 786 $ 59,201 1m Fargo-Galesburg-Oak Grove - CWIP 3022 $ 6,097,868 $ 5,669,021 $ 4,937,941 $ (731,080) $ (9,843) $ (740,923) 1n Fargo-Galesburg-Oak Grove - Plant in Service - No HCS $ 844,203 $ 784,832 $ 1,117,750 $ 332,918 $ 4,482 $ 337,400 1o Fargo-Galesburg-Oak Grove - Land - No HCS $ 485,892 $ 451,721 $ 440,852 $ (10,869) $ (146) $ (11,015) 1p Pawnee-Pana - CWIP 3169 $ 7,536,882 $ 7,006,833 $ 6,614,602 $ (392,231) $ (5,281) $ (397,512) 1q Pawnee-Pana - Plant in Service - No HCS $ 486,482 $ 452,269 $ 1,418,901 $ 966,632 $ 13,015 $ 979,647 1r Pawnee-Pana - Land - No HCS $ 556,817 $ 517,658 $ 430,130 $ (87,528) $ (1,178) $ (88,706) 1s Adair-Palmyra - CWIP 3170 $ 4,531,940 $ 4,213,221 $ 3,463,383 $ (749,838) $ (10,096) $ (759,934) 1t Adair-Palmyra - Plant in Service - No HCS $ 397,433 $ 369,483 $ 1,162,663 $ 793,180 $ 10,679 $ 803,859 1u Adair-Palmyra - Land - No HCS $ 110,073 $ 102,332 $ 100,080 $ (2,252) $ (30) $ (2,282) 3 Subtotal $ 127,513,156 $ 118,545,498 $ 119,507,672 4 Under/(Over) Recovery $ 962,174 $ 12,956 $ 975,130 5 Applicable Interest rate per month (expressed to four decimal places) Interest Rate to be updated through July 2017 0.0561% Amount excludes True-Up Adjustment, as reported in True-Up Year projected Attachment MM, page 2, column 15. 2 Rounded to whole dollars.

Atxi 2016 MVP SPEND Ameren MVPs Ameren Name 2016 CAPEX MTEP #s MTEP Description Illinois Rivers $354 million   2237 Pana - Mt. Zion - Kansas - Sugar Creek 345 kV line 2239 Sidney to Rising 345 kV line 3017 Palmyra-Quincy-Meredosia - Ipava & Meredosia-Pawnee 345 kV Line 3169 Pawnee to Pana - 345 kV Line 3170 New Palmyra Substation (Maywood) Spoon River $36 million 3022 Fargo-Galesburg-Oak Grove 345 kV Line Mark Twain $9 million 2248 Adair - Ottumwa 345 Adair-Palmyra 345 kV Line

MVP Facilities in service Illinois Rivers   All 10 Substations 4 of 9 Line Segments Austin Faraday-Pana (32.4 mi) Faraday Sidney-Rising (24.2 mi) Herleman Maywood-Herleman (14.7 mi) Ipava Herleman-Meredosia (46.6 mi) Kansas Maywood 2 of 3 River Crossings Meredosia Herleman-Maywood Pana Meredosia-Herleman Rising Sidney Spoon River Fargo Substation Sandburg Substation

Additional information Additional questions can be sent to Ameren at: MISOFormulaRates@ameren.com MISO Web Links Transmission Pricing - Attachments O, GG & MM Information https://www.misoenergy.org/MarketsOperations/TransmissionSettlements/Pages/TransmissionPricing.aspx Ameren OASIS http://www.oasis.oati.com/AMRN/index.html MTEP 16 https://www.misoenergy.org/Planning/TransmissionExpansionPlanning/Pages/MTEP16.aspx MTEP 17 https://www.misoenergy.org/Planning/TransmissionExpansionPlanning/Pages/MTEP17.aspx Schedule 26 & 26-A Indicative Charges https://www.misoenergy.org/Planning/TransmissionExpansionPlanning/Pages/MTEPStudies.aspx