1. 2018 Annual Attachment O Stakeholder Meeting Ameren Missouri
July 10, 2018

2. Agenda
Primary purpose is to review AMMO Pricing Zone Historical 2017 Transmission Rate Calculations which became effective June 1, 2018
Protocol Timeline
Attachment O Template Changes
ROE Complaint Cases
Comparison to Previous Revenue Requirement
2018 AMMO Pricing Zone NITS Charge

3. Protocol timeline Date Action (Historical) June 1
Posting of annual update
Information exchange period begins.
Review period begins.
September 1
Deadline for annual meeting
November 1
Deadline for joint meeting on regional cost-shared projects
December 1
Deadline for Interested Parties to submit information requests
January 10
Deadline for Transmission Owners to respond to information requests
January 31
Deadline for Interested Parties to submit Informal Challenges
February 28
Deadline for Transmission Owners to respond to Informal Challenges
Any rate changes agreed to by the Transmission Owner will be included in the Information Filing and will be reflected in the Annual Update for the following Rate Year.
March 15
Transmission Owners submit informational filing to the Commission.
March 31
Deadline for Interested Parties to file Formal Challenge at the Commission

4. Ameren Missouri Attachment O tariff changes
Docket ER
FERC Order on May 31, 2018
Effective June 1, 2018 for Ameren Missouri
Approved company-specific Attachment O for Ameren Missouri
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 Update including these changes was posted on Ameren’s OASIS and is included in the rates effective June 1, 2018
These tariff changes resulted in an increase of $1,063,389 to the net Attachment O revenue requirement and an increase of $145,406 to the Attachment GG revenue requirement

5. Roe complaint 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 with a 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. Current effective ROE is 10.82%
Roe complaint
Current effective ROE is 10.82%
Effective revenue requirement will be adjusted as needed for new ROE upon receipt of Order in 2nd Complaint Case
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.
Point-to-point refunds made by Ameren Missouri are treated as an adjustment in the 2016 Annual Update
Phase 2 related to the ROE impact on true-ups calculations for forward looking TOs. These were settled in June 2017.
No Phase 2 schedule 9 refunds for Ameren Missouri since they are historical
Refunds for Schedules 7, 8, 26, 37, 38, 26A were completed by MISO
Refunds for Schedule 9 were completed by Ameren
Small point-to-point amounts related to Phase 2 of ROE are included in the 2017 True-Up.
Schedule 9 Refund amounts and supporting documents are posted on OASIS

7. June 2017 vs June 2018 Calculation
Ameren Missouri
Revenue Requirement
June 2017 vs June 2018 Calculation

8. Ameren Missouri June 2018 Calculation
Rate Base
Page.Line
Jun-17
Jun-18
Change
Percent
2.6
Total Gross Plant
1,176,985,925
1,229,731,470
52,745,544 4%
2.12
Total Accum Depreciation
337,277,231
358,956,337
21,679,107 6%
2.18
TOTAL NET PLANT
839,708,694
870,775,132
31,066,438
ADJUSTMENTS TO RATE BASE
2.20
Account No. 282
(241,157,155)
(257,137,887)
(15,980,731) 7%
2.21
Account No. 283
(6,231,888)
(6,584,410)
(352,522)
2.22
Account No. 190
6,048,866
12,695,516
6,646,650
110%
2.25
Land Held for Future Use
4,741,655
6,181,437
1,439,782
30%
2.26
CWC
4,446,739
4,367,355
(79,385)
-2%
2.27
Materials & Supplies
4,105,744
3,958,847
(146,898)
-4%
2.28
Prepayments
1,210,298
1,183,365
(26,934)
TOTAL ADJUSTMENTS
(226,835,740)
(235,335,777)
(8,500,038)
2.30
TOTAL RATE BASE
612,872,955
635,439,355
22,566,400

9. Ameren Missouri June 2018 Calculation
Expenses
Page.Line
Jun-17
Jun-18
Change
Percent
O&M
3.1
Transmission
77,077,746
92,937,081
15,859,335
21%
3.1a
Less LSE Expenses
6,676,917
6,738,357
61,440 1%
3.2
Less Account 565
43,363,135
59,557,269
16,194,134
37%
3.3
A&G
7,899,056
7,706,698
(192,358)
-2%
3.4
Less FERC Annual Fees -
N/A
3.5
Less EPRI, ect.
634,804
694,050
59,246 9%
3.5a
Plus Trans. Reg. Comm. Exp
32,280
107,355
75,075
233%
3.7
Transmission Lease Payments
1,239,690
1,177,380
(62,310)
-5%
3.8
TOTAL O&M
35,573,915
34,938,838
(635,078)
3.12
TOTAL DEPRECIATION
26,760,281
30,278,318
3,518,037
13%
TAXES
3.13
Payroll
607,758
649,658
41,900 7%
3.16
Property
10,222,922
10,406,484
183,562 2%
3.18
Other
9,987
41,416
31,429
315%
3.27
Income Taxes*
20,442,429
12,589,728
(7,852,701)
-38%
TOTAL TAXES
31,283,096
23,687,286
(7,595,811)
-24%
TOTAL EXPENSES
93,617,292
88,904,441
(4,712,851)
*The June 2017 Income Taxes above are at the old Federal Income Tax Rate of 35%. The June 2018 amounts reflect the current Federal Income Tax Rate of 21% as a result of the Tax Cuts and Jobs Act which became effective January 1, The June 2018 income taxes also include the adjustment related to Docket ER (discussed on slide 4).

10. Ameren Missouri June 2018 Calculation
Capital Structure
Capital Structure - June 2017
Page.Line $ %
Cost
Weighted
4.27
Long Term Debt
3,737,276,000
48%
0.0522
0.0249
4.28
Preferred Stock
80,759,500 1%
0.0424
0.0004
4.29
Common Stock
4,009,795,947
51%
0.1082
0.0554
4.3
Total
7,827,831,447
100%
0.0808
Capital Structure - June 2018
3,712,276,000
0.0512
0.0244
4,000,217,417
0.0555
7,793,252,917
0.0803
Change in Return %

11. Ameren Missouri June 2018 Calculation
Revenue Requirement
Page.Line
Jun-17
Jun-18
Change
Percent
2.30
TOTAL RATE BASE
612,872,955
635,439,355
22,566,400 4%
4.30
Rate of Return
0.0808
0.0803
(0.0004)
-1%
3.28
Return
49,506,223
51,054,978
1,548,755 3%
Total Expenses
93,617,292
88,904,441
(4,712,851)
-5%
3.29
TOTAL GROSS REV. REQ.
143,123,514
139,959,419
(3,164,095)
-2%
3.30
Less ATT. GG Adjustment
15,562,140
14,604,193
(957,947)
-6%
3.30a
Less ATT. MM Adjustment -
N/A
3.31
GROSS REV. REQ. UNDER ATT. O
127,561,375
125,355,226
(2,206,149)

12. Ameren Missouri June 2018 Calculation
Net Revenue Requirement
Page.Line
Jun-17
Jun-18
Change
Percent
1.1
Gross Revenue Requirement
127,561,375
125,355,226
-2,206,149
-2%
1.6
Total Revenue Credits
6,377,122
6,176,051
-201,071
-3%
1.6c
Total Prior Period Adjustment (with interest)
605,636
-5,871
-611,507
-101%
1.7
NET REVENUE REQUIREMENT
121,789,889
119,173,304
-2,616,585
The Prior Period Adjustments for June 2017 relate to the point-to-point portion of the ROE refund required per the Order in Docket No. EL14-12 (Phase 1)
The Prior Period Adjustments for June 2018 relate to the point-to-point portion of the ROE refund required per the Order in Docket No. EL14-12 (Phase 2)

13. Ameren Missouri June 2018 Calculation
AMMO Schedule 9 Rate Calculation
Page.Line
Jun-17
Jun-18
Change
Percent
1.7
Net Revenue Requirement
121,789,889
119,173,304
-2,616,585
-2%
1.15
Ameren Missouri Divisor
6,317,790
6,206,891
(110,899)
Annual Cost ($/kW/Yr)
19.277
19.200
(0.077) 0%
Network & P-to-P Rate ($/kW/Mo)
1.606
1.600
(0.006)
The divisor excludes the Southeast Missouri load included in the Entergy Arkansas, Inc. (EAI) pricing zone.

14. Ameren Missouri June 2018 Calculation
Attachment GG Calculation - Page 1
(1)
(2)
(3)
(4)
Attachment O
Line
Page, Line, Col.
Transmission
Allocator
No. 1
Gross Transmission Plant - Total
Attach O, p 2, line 2 col 5 (Note A)
1,201,003,944 2
Net Transmission Plant - Total
Attach O, p 2, line 14 and 23b col 5 (Note B)
853,685,594
O&M EXPENSE 3
Total O&M Allocated to Transmission
Attach O, p 3, line 8 col 5
34,938,838 4
Annual Allocation Factor for O&M
(line 3 divided by line 1 col 3)
2.91%
GENERAL AND COMMON (G&C) DEPRECIATION EXPENSE 5
Total G&C Depreciation Expense
Attach O, p 3, lines 10 & 11, col 5 (Note H)
1,405,048 6
Annual Allocation Factor for G&C Depreciation Expense
(line 5 divided by line 1 col 3)
0.12%
TAXES OTHER THAN INCOME TAXES 7
Total Other Taxes
Attach O, p 3, line 20 col 5
11,097,557 8
Annual Allocation Factor for Other Taxes
(line 7 divided by line 1 col 3)
0.92% 9
Annual Allocation Factor for Expense
Sum of line 4, 6, and 8
3.95%
INCOME TAXES 10
Total Income Taxes
Attach O, p 3, line 27 col 5
12,589,728 11
Annual Allocation Factor for Income Taxes
(line 10 divided by line 2 col 3)
1.47%
RETURN 12
Return on Rate Base
Attach O, p 3, line 28 col 5
51,054,978 13
Annual Allocation Factor for Return on Rate Base
(line 12 divided by line 2 col 3)
5.98% 14
Annual Allocation Factor for Return
Sum of line 11 and 13
7.46%

15. Ameren Missouri June 2018 Calculation
Attachment GG Calculation - Page 2
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
Line No.
Project Name
MTEP Project Number
Project Gross Plant
Annual Allocation Factor for Expense
Annual Expense Charge
Project Net Plant
Annual Allocation Factor for Return
Annual Return Charge
Project Depreciation Expense
Annual Revenue Requirement
True-Up Adjustment
Network Upgrade Charge
(Note C)
(Page 1 line 9)
(Col. 3 * Col. 4)
(Note D)
(Page 1 line 14)
(Col. 6 * Col. 7)
(Note E)
(Sum Col. 5, 8 & 9)
(Note F)
Sum Col. 10 & 11 (Note G) 1a
Big River-Rockwood 138 kV
152
$15,650,433
3.95%
$618,215
$13,617,069
7.46%
$1,015,192
$332,689
$1,966,096 $ 1b
Reconductor Sioux-Huster-1 and kV
1240
$15,553,957
$614,404
$13,011,572
$970,050
$403,455
$1,987,909 1c
Gray Summit : 2nd 345/138 kV Transformer
2061
$22,410,811
$885,260
$19,436,641
$1,449,057
$407,469
$2,741,787 1d
Lutesville: Northwest Cape 345/161 kV substation and new lines
2306
$58,887,812
$2,326,156
$56,624,642
$4,221,529
$1,360,716
$7,908,401 2
Annual Totals
$14,604,193 $0 3
Rev. Req. Adj For Attachment O

16. Significant transmission projects in 2017 and 2018
Completed in 2017
Project Name
Total Cost
Intelligrid
$16 Million
Sioux-Viele
$6 Million
Page-Mason
To Be Completed in 2018
Project Name
Total Cost
Intelligrid
$16 Million
Venice-Campbell
$9 Million
CIP V5
$7 Million
Rush Island-Tyson
Lutesville-St. Francois
$5 Million

17. 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
Study/mtepstudytype:Indicative Rate Reports