1. 2017 Attachment O True-Up Stakeholder Meeting Ameren Illinois Company
August 8, 2018

2. Purpose is to review AIC 2017 Transmission Rate True-Up Calculations
Agenda
Purpose is to review AIC 2017 Transmission Rate True-Up Calculations
Protocol Timeline
Attachment O Template Changes
ROE Complaint Cases and Impact on True-up calculations
2017 True-Up Calculation
Total Revenue Requirement Comparison – Projected vs Actual
Attachment O/Schedule 9 True-up
Attachment GG/Schedule 26 True-up
Attachment MM/Schedule 26-A True-up
2017 Significant Projects Placed In Service
An additional meeting will held to review the 2019 Projected Transmission Rate calculations. Tentatively set for September 27, 2018.

3. (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

4. Ameren Illinois Attachment O Changes
Docket ER
FERC Order on May 31, 2018
Effective January 1, 2018 for Ameren Illinois
Approved additional lines in the Income Tax Section (Page 3, Lines 24a/24b and 26a/26b)
Modification to return to (or recover from) customers excess (or deficient) accumulated deferred income taxes (ADIT) resulting from tax law or rate changes
An adjustment to recognize the effects of permanent differences between tax accounting and financial reporting, such as those associated with the equity component of Allowance for Funds Used During Construction (AFUDC) Equity
Revised 2017 Annual True-Up including these changes was posted on Ameren’s Oasis
These tariff changes resulted in decreases of $210,328, $16,613 and $15,770 to the Net Attachment O revenue requirement, Attachment GG revenue requirement and Attachment MM revenue requirement, respectively

5. 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 may 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%)

6. MISO ROE for the 2017 True-Up is 10.82%
ROE complaints
MISO ROE for the 2017 True-Up is 10.82%
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 completed by Ameren
Schedule 9 Refund amounts and supporting documents are posted on Ameren’s OASIS

7. AIC Revenue Requirement Comparison
Projected 2017 vs Actual 2017

8. Aic 2017 rate base 2017 Projection 2017 Actual Change Percent 2.6
Page.Line
2017 Projection
2017 Actual
Change
Percent
2.6
Total Gross Plant
2,296,555,948
2,255,649,628
-40,906,319
-2%
2.12
Total Accum Depreciation
525,122,593
505,542,832
-19,579,761
-4%
2.18
TOTAL NET PLANT
1,771,433,355
1,750,106,796
-21,326,559
-1%
2.18a
100% CWIP RECOVERY
8,709,958
3,003,443
-5,706,515
-66%
ADJUSTMENTS TO RATE BASE
N/A
2.20
Account No. 282
-484,788,908
-459,835,685
24,953,224
-5%
2.21
Account No. 283
-10,255,343
-9,578,047
677,296
-7%
2.22
Account No. 190
49,214,591
37,402,434
-11,812,156
-24%
2.23
Account No. 255
2.25
Land Held for Future Use
2,484,054
2,442,435
-41,619
2.26
CWC
6,210,229
6,331,316
121,087 2%
2.27
Materials & Supplies
13,677,702
13,973,223
295,521
2.28
Prepayments
1,638,369
1,936,099
297,730
18%
TOTAL ADJUSTMENTS
-421,819,306
-407,328,224
14,491,082
-3%
2.30
TOTAL RATE BASE
1,358,324,006
1,345,782,015
-12,541,991

9. Aic 2017 expenses
Page.Line
2017 Projection
2017 Actual
Change
Percent
O&M
3.1
Transmission
59,336,832
55,185,538
-4,151,294
-7%
3.1a
Less LSE Expenses
1,703,652
1,654,502
-49,150
-3%
3.2
Less Account 565
23,725,630
18,889,547
-4,836,083
-20%
3.3
A&G
15,413,506
16,055,403
641,897 4%
3.4
Less FERC Annual Fees
N/A
3.5
Less EPRI, ect.
243,164
266,259
23,094 9%
3.5a
Plus Trans. Reg. Comm. Exp
603,944
219,897
-384,047
-64%
3.8
TOTAL O&M
49,681,835
50,650,530
968,695 2%
3.12
TOTAL DEPRECIATION
42,958,714
42,161,654
-797,060
-2%
TAXES
3.13
Payroll
893,601
779,468
-114,133
-13%
3.16
Property
1,364,211
1,436,554
72,343 5%
3.18
Other
481,037
498,416
17,379
3.27
Income Taxes *
50,884,298
51,762,595
878,297
TOTAL TAXES
53,623,147
54,477,033
853,886
TOTAL EXPENSES
146,263,697
147,289,217
1,025,521 1%
* The 2017 actual income taxes include the adjustments related to Docket ER (discussed on slide 4).

10. Aic 2017 Capital structure 2017 Projection $ % Cost Weighted 4.27
Page.Line $ %
Cost
Weighted
4.27
Long Term Debt
2,665,883,538
47%
0.0550
0.0260
4.28
Preferred Stock
61,721,350 1%
0.0490
0.0005
4.29
Common Stock
2,908,148,803
52%
0.1082
0.0558
4.30
Total
5,635,753,692
100%
0.0824
2017 Actual
2,628,383,538
0.0542
0.0254
61,632,375
0.0491
2,908,901,913
0.0562
5,598,917,827
0.0822
Change in Return %

11. Aic 2017 total revenue requirement
Page.Line
2017 Projection
2017 Actual
Change
Percent
2.30
TOTAL RATE BASE
1,358,324,006
1,345,782,015
-12,541,991
-1%
4.30
Rate of Return
8.24%
8.22%
-0.02% 0%
3.28
Return
111,915,393
110,592,532
-1,322,861
Total Expenses
146,263,697
147,289,217
1,025,521 1%
3.29
TOTAL GROSS REV. REQ.
258,179,090
257,881,749
-297,340
3.30
Less ATT. GG Adjustment
16,346,548
16,515,543
168,995
3.30a
Less ATT. MM Adjustment
14,052,764
13,795,822
-256,942
-2%
3.31
GROSS REV. REQ. UNDER ATT. O
227,779,777
227,570,384
-209,393

12. Aic 2017 Net revenue requirement for Schedule 9
Page.Line
2017 Projection
2017 Actual
Change
Percent
1.1
Gross Revenue Requirement
227,779,777
227,570,384
-209,393 0%
1.6
Total Revenue Credits
13,682,453
12,248,816
-1,433,637
-10%
1.6a
Historic Year Actual ATRR
163,559,846
163,550,117
(9,729)
1.6b
Projected ATRR from Prior Year
158,036,243
1.6c
Prior Year ATRR True-Up
5,523,603
5,513,874
1.6d
Prior Year Divisor True-Up
3,916,998
3,851,673
(65,325)
-2%
1.6e
Interest on Prior Year True-Up
61,855
125,785
63,930
103%
1.7a
NET REVENUE REQUIREMENT
223,599,780
224,812,900
1,213,120 1%
1.7b
Prairie Power
N/A
1.7
AIC Adjusted Revenue Requirement .

13. Aic 2017 attachment o true-up for Schedule 9
Attachment O 2017 True-up calculation (Schedule 9)
Net Actual 2017 Rev Req (Actual Attach O, Pg 1, Line 7)
$224,812,900
Net Projected 2017 Rev Req (Projected Attach O, Pg 1, Line 7)
$223,599,780
Under/(Over) Collection of 2017 Net Rev Req
$1,213,120
Historic Year Actual Divisor for Transmission Owner (Attach O, Pg 1, Line 15)
6,859,419
Proj'd Yr Divisor for Transmission Owner (Projected Attach O, Pg 1, Line 15)
7,315,667
Difference between Historic & Projected Yr Divisor
456,248
Prior Year Projected Annual Cost ($ per kw per yr) $
Under/(Over) Collection of 2017 Divisor True-up
$13,944,992
Total Under/(Over) Recovery
$15,158,112
Monthly Interest Rate (Over collection = FERC rate, Under collection = company rate)
0.1210%
Interest For 24 Months
$440,192
Total 2017 Attachment O True-up Under/(Over) Recovery (To be included in Projected 2019)
$15,598,304

14. Aic 2017 attachment gg True-up by Project

15. Aic 2017 attachment MM true-up by Project

16. Aic 2017 attach GG & MM true-up for Schedule 26 & 26-A
Attachment GG 2017 True-up ( Schedule 26)
Actual Attachment GG Rev Req for True-Up Year (Actual Attach GG, pg 2, col 10) 1
$16,515,543
Actual Attachment GG Revenues Received for 20171
$16,557,667
Under/(Over) Recovery of 2017 GG Rev Req
($42,124)
Monthly Interest Rate (Over collection = FERC rate, Under collection = company rate)
0.3260%
Interest For 24 Months
($3,296)
Total 2017 Attachment GG True-up Under/(Over) Recovery
($45,420)
1 Amount excludes True-Up Adjustment, as reported in True-Up Year projected Attachment GG, page 2, column 11.
Attachment MM 2017 True-up (Schedule 26-A)
Actual Attachment MM Rev Req for True-Up Year (Actual Attach GG, pg 2, col 14) 1
$13,795,822
Actual Attachment MM Revenues for 20171
$13,112,805
Under/(Over) Recovery of 2017 MM Rev Req
$683,017
0.1210%
$19,835
Total 2017 Attachment MM True-up Under/(Over) Recovery
$702,852
1 Amount excludes True-Up Adjustment, as reported in True-Up Year projected Attachment MM, page 2, column 15.

17. 2017 Significant transmission projects added to plant
Project Name
Total Cost
($ Millions)
CS014 - NERC CIP V5 - LOW
$22.1
IT050 - E Galesburg-E Kewanee
$19.0
IT031 - Cahokia-Dupo Ferry-Buck Knob
$16.0
IT096 - West Frankfort - Ina
$14.1
IT030 - Baldwin Ring Bus & Line Split
$13.3
IT091 - Bee Hollow Rebuild
$11.2
IL001 - Illinois Rivers
$10.6
IT048 - Lawrenceville S-Robinson Marathon
$10.5
IT045 - S Belleville-T
$10.3
IT033 - Searitt Switching Station
$9.6
CS012 - Intelligrid
$9.5
IT051 - Gibson City-Paxton E
$9.0
IT049 - Hoopeston W-Paxton E
$8.5
IT097 - Pana North - Moweaqua
$7.7
IT053 - Turkey Hill-Ashley
$7.6
IT036 - Hickok Breaker Station TP728
$7.1
IT035 - Monument Program
$6.8
IT086 - Huff Substation Ring Bus (TP707)
$5.7
IT046 - Jerseyville Northest-Meredosia East
$5.4
IT047 - S Belleville-Centreville
$5.1

18. Additional information
Additional questions can be sent to Ameren at:
MISO Web Links
Transmission Pricing - Attachments O, GG & MM Information
Ameren OASIS
MTEP 18
MTEP 17
Schedule 26 & 26-A Indicative Charges