Vanguard Index Funds - Vanguard Mid-Cap Index Fund Admiral Class
US ˙ MUTF ˙ US9229086452

SecurityVIMAX / Vanguard Index Funds - Vanguard Mid-Cap Index Fund Admiral Class
InstitutionArvest Bank Trust Division
Latest Disclosed Ownership907 shares
Latest Disclosed Value $ 323,177
Arvest Bank Trust Division reports 19.52% decrease in ownership of VIMAX / Vanguard Index Funds - Vanguard Mid-Cap Index Fund Admiral Class

On May 13, 2026 - Arvest Bank Trust Division filed a 13F-HR form disclosing ownership of 907 shares of Vanguard Index Funds - Vanguard Mid-Cap Index Fund Admiral Class (US:VIMAX) valued at $323,177 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 9, 2026 disclosing 1,127 shares of Vanguard Index Funds - Vanguard Mid-Cap Index Fund Admiral Class. This represents a change in shares of -19.52% during the quarter. The current value of the position is $280,626 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-13 2026-03-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 907 -220 -19.52 323 -20.25 0.0176
2026-02-09 2025-12-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,127 -159 -12.36 406 -13.46 0.0220
2025-11-07 2025-09-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,286 -44 -3.31 468 1.52 0.0260
2025-08-08 2025-06-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,330 -501 -27.36 462 -21.33 0.0269
2025-05-14 2025-03-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,831 0 0.00 587 -2.01 0.0371
2025-02-13 2024-12-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,831 165 9.90 599 9.93 0.0361
2024-11-25 2024-09-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,666 -1,584 -48.74 545 -42.92 0.0314
2021-11-12 2021-09-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 3,250 218 7.19 953 6.84 0.0535
2021-08-19 2021-06-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 3,032 968 46.90 892 57.60 0.0492
2021-04-13 2021-03-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 2,064 -33 -1.57 566 5.20 0.0329
2021-02-17 2020-12-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 2,097 2,097 538 0.0334
2020-11-30 2020-09-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 0 -2,170 -100.00 0 -100.00
2020-08-21 2020-06-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 2,170 -2,148 -49.75 440 -37.50 0.0326
2020-04-14 2020-03-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 4,318 164 3.95 704 -23.23 0.0651
2020-01-14 2019-12-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 4,154 -19 -0.46 917 5.77 0.0589
2019-10-18 2019-09-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 4,173 3,122 297.05 867 299.54 0.0595
2019-07-19 2019-06-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,051 -1,119 -51.57 217 -49.77 0.0148
2019-04-12 2019-03-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 2,170 73 3.48 432 20.67 0.0299
2019-01-18 2018-12-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 2,097 -311 -12.92 358 -26.94 0.0285
2018-10-30 2018-09-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 2,408 -6 -0.25 490 4.03 0.0332
2018-07-18 2018-06-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 2,414 479 24.75 471 27.30 0.0335
2018-05-11 2018-03-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,935 459 31.10 370 30.74 0.0262
2018-01-22 2017-12-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,476 14 0.96 283 6.39 0.0198
2017-10-06 2017-09-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,462 0 0.00 266 3.10 0.0190
2017-07-12 2017-06-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,462 0 0.00 258 2.38 0.0196
2017-04-17 2017-03-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,462 0 0.00 252 5.88 0.0198
2017-01-09 2016-12-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,462 0 0.00 238 1.71 0.0191
2016-10-07 2016-09-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,462 -51 -3.37 234 0.86 0.0194
2016-08-16 2016-06-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,513 0 0.00 232 2.20 0.0200
2016-04-27 2016-03-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,513 0 0.00 227 0.89 0.0192
2016-02-08 2015-12-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,513 84 5.88 225 8.70 0.0196
2015-10-13 2015-09-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,429 0 0.00 207 -8.00 0.0187
2015-07-07 2015-06-30 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,429 -237 -14.23 225 -15.41 0.0190
2015-04-21 2015-03-31 13F/A-2 VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,666 1,666 266 0.0228
2015-04-21 2015-03-31 13F VANGUARD INDEX FDS MDCAP INDX ADM 922908645 1,666 257 0.0225
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.