American Electric Power Company, Inc. (AEP) Stock Total Returns
Growth of $10,000 chart
2021-04-14 to 2026-04-14 to
$
%
%
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Investment Performance
Final Value
$17,982
Total Return
79.82%
CAGR
12.45%
Dividends
$2,107.89
Yield on Cost
21.08%
Rolling Returns
1-Month (21 Trading Days)
| Average | +1.10% |
| Median | +1.33% |
| Best | +16.56% |
| Worst | -20.19% |
| % of Windows Positive | 57.5% |
1-Year (252 Trading Days)
| Average | +11.48% |
| Median | +14.37% |
| Best | +46.49% |
| Worst | -23.49% |
| % of Windows Positive | 71.2% |
3-Year (756 Trading Days)
| Average | +27.36% |
| Median | +23.58% |
| Best | +67.91% |
| Worst | -0.20% |
| % of Windows Positive | 99.8% |
Risk Metrics
| Maximum Drawdown | -30.09% |
| Average Drawdown | -8.42% |
| Drawdown Duration | 474 Trading Days |
| Sortino Ratio | 1.00 |
| Calmar Ratio | 0.41 |
| CVaR (5%) | -2.78% |
Yearly Returns
| Year | Percentage | Abs. Return | Dividends | Taxes | Trans. Costs |
|---|---|---|---|---|---|
| 2026 partial | +18.21% (+79.95% ann.) | +$1820.96 | $82.39 | $16.48 | $0.13 |
| 2025 | +28.47% | +$2846.57 | $409.90 | $81.98 | $0.66 |
| 2024 | +17.22% | +$1721.97 | $445.19 | $89.04 | $0.71 |
| 2023 | -11.68% | $1168.41 | $359.02 | $71.80 | $0.57 |
| 2022 | +9.63% | +$962.69 | $359.90 | $71.98 | $0.58 |
| 2021 | +9.90% | +$990.46 | $364.16 | $72.83 | $0.58 |
| 2020 | -9.61% | $961.35 | $303.35 | $60.67 | $0.49 |
| 2019 | +29.70% | +$2969.68 | $366.19 | $73.24 | $0.59 |
| 2018 | +4.62% | +$461.70 | $347.88 | $69.58 | $0.56 |
| 2017 | +20.10% | +$2009.84 | $383.72 | $76.74 | $0.61 |
| 2016 | +11.13% | +$1112.68 | $393.73 | $78.74 | $0.63 |
| 2015 | -1.06% | $105.86 | $358.09 | $71.62 | $0.57 |
| 2014 | +34.02% | +$3401.91 | $439.65 | $87.93 | $0.70 |
| 2013 | +13.21% | +$1321.28 | $462.66 | $92.53 | $0.74 |
| 2012 | +7.21% | +$721.05 | $461.64 | $92.33 | $0.74 |
| 2011 | +19.57% | +$1956.59 | $522.22 | $104.44 | $0.83 |
| 2010 | +7.58% | +$758.35 | $499.17 | $99.83 | $0.80 |
| 2009 | +9.16% | +$916.48 | $500.88 | $100.18 | $0.80 |
| 2008 | -26.02% | $2601.70 | $356.30 | $71.26 | $0.57 |
| 2007 | +12.30% | +$1230.16 | $374.82 | $74.96 | $0.60 |
| 2006 | +18.61% | +$1860.73 | $409.63 | $81.93 | $0.66 |
| 2005 | +11.45% | +$1144.87 | $418.50 | $83.70 | $0.67 |
| 2004 | +16.49% | +$1648.75 | $464.92 | $92.98 | $0.74 |
| 2003 | +17.67% | +$1767.06 | $616.31 | $123.26 | $0.99 |
| 2002 | -33.74% | $3374.38 | $561.29 | $112.26 | $0.90 |
| 2001 | -2.33% | $232.63 | $524.37 | $104.87 | $0.84 |
| 2000 | +52.62% | +$5262.16 | $762.90 | $152.58 | $1.22 |
| 1999 | -28.26% | $2825.83 | $519.02 | $103.80 | $0.83 |
| 1998 | -5.07% | $506.78 | $472.01 | $94.40 | $0.75 |
| 1997 | +31.25% | +$3125.09 | $593.87 | $118.77 | $0.95 |
| 1996 | +6.26% | +$626.27 | $602.81 | $120.56 | $0.96 |
| 1995 | +30.16% | +$3016.19 | $745.70 | $149.14 | $1.19 |
| 1994 | -6.01% | $601.16 | $660.84 | $132.17 | $1.06 |
| 1993 | +18.17% | +$1816.79 | $739.27 | $147.85 | $1.18 |
| 1992 | +2.64% | +$264.38 | $716.76 | $143.35 | $1.15 |
| 1991 | +30.65% | +$3065.10 | $879.45 | $175.89 | $1.41 |
| 1990 | -9.38% | $938.17 | $745.27 | $149.06 | $1.19 |
| 1989 | +27.43% | +$2743.33 | $657.45 | $131.49 | $1.05 |
| 1988 | +10.99% | +$1098.99 | $903.97 | $180.80 | $1.45 |
| 1987 | +2.12% | +$211.74 | $871.88 | $174.37 | $1.39 |
| 1986 | +24.41% | +$2441.27 | $982.14 | $196.42 | $1.57 |
| 1985 | +21.45% | +$2145.49 | $1104.38 | $220.88 | $1.76 |
| 1984 | +36.37% | +$3636.72 | $1372.69 | $274.54 | $2.20 |
| 1983 | +6.19% | +$619.21 | $1320.37 | $264.07 | $2.12 |
| 1982 | +21.37% | +$2136.71 | $1449.42 | $289.88 | $2.32 |
| 1981 | +7.56% | +$756.39 | $1397.23 | $279.44 | $2.23 |
| 1980 | +1.55% | +$155.14 | $954.75 | $190.95 | $1.53 |
| 1979 | -7.87% | $787.43 | $1069.11 | $213.82 | $1.72 |
| 1978 | -6.67% | $666.67 | $900.28 | $180.06 | $1.45 |
| 1977 | +2.26% | +$225.54 | $834.49 | $166.89 | $1.34 |
| 1976 | +30.36% | +$3036.05 | $985.74 | $197.14 | $1.58 |
| 1975 | +59.25% | +$5924.54 | $1439.43 | $287.87 | $2.30 |
| 1974 | -39.09% | $3908.73 | $599.77 | $119.96 | $0.95 |
| 1973 | -11.94% | $1194.06 | $629.31 | $125.86 | $1.01 |
| 1972 | +3.69% | +$369.46 | $591.75 | $118.35 | $0.95 |
| 1971 | +11.79% | +$1178.86 | $606.97 | $121.40 | $0.97 |
| 1970 partial | -2.11% (-2.13% ann.) | $211.43 | $550.44 | $110.09 | $0.88 |
Market Regimes
| Regime | Period | Percentage | Annual | Abs. Return | Dividends | Taxes | Trans. Costs |
|---|---|---|---|---|---|---|---|
| Dot-com bubble / TMT mania | August 9, 1995 – March 10, 2000 | -5.69% | -1.27% | $569.19 | $3502.39 | $700.48 | $5.60 |
| Dot-com bust / post-bubble disinflation scare | March 13, 2000 – October 9, 2002 | -24.86% | -10.51% | $2485.75 | $2390.03 | $478.00 | $3.82 |
| China-WTO / housing-credit / commodity boom | October 10, 2002 – October 9, 2007 | +175.19% | +22.46% | +$17519.10 | $4037.04 | $807.41 | $6.46 |
| GFC / deleveraging / dollar shortage | October 10, 2007 – March 9, 2009 | -46.24% | -35.55% | $4623.86 | $527.56 | $105.51 | $0.84 |
| Policy-led rebound / euro-sovereign-crisis overlay | March 10, 2009 – July 25, 2012 | +90.51% | +21.04% | +$9051.11 | $2476.60 | $495.32 | $3.96 |
| Secular stagnation / QE / low inflation / duration bull | July 26, 2012 – February 19, 2020 | +210.00% | +16.13% | +$20999.79 | $4782.42 | $956.48 | $7.65 |
| Pandemic shock / liquidity crash | February 20, 2020 – March 23, 2020 | -31.63% | -98.70% | $3162.73 | $0.00 | $0.00 | $0.00 |
| Policy bazooka / monetary euphoria | March 24, 2020 – November 6, 2020 | +27.91% | +48.59% | +$2790.76 | $195.00 | $39.00 | $0.31 |
| Reopening reflation / fiscal boom / supply bottlenecks | November 9, 2020 – November 29, 2021 | -5.06% | -4.80% | $505.71 | $417.41 | $83.48 | $0.67 |
| Inflation shock / duration crash / aggressive tightening | November 30, 2021 – November 9, 2022 | +11.30% | +12.04% | +$1130.28 | $395.06 | $79.01 | $0.63 |
| Disinflation rebound / AI-led narrow bull / higher-for-longer | November 10, 2022 – September 17, 2024 | +20.06% | +10.37% | +$2005.96 | $670.86 | $134.17 | $1.07 |
| Disinflationary easing / resilient growth / AI capex under oil-shock test partial | September 18, 2024 – April 14, 2026 | +36.74% | +22.07% | +$3673.53 | $554.47 | $110.89 | $0.89 |
Dividend History
Annual Dividends Per Share
TTM Yield
—
Consecutive Years Paid
— current
Consecutive Years of Growth
— current
| Date | Per Share | Yield % |
|---|---|---|
| 1970-02-04 | $0.4100 | 1.44% |
| 1970-05-05 | $0.4100 | 1.53% |
| 1970-08-04 | $0.4100 | 1.64% |
| 1970-11-04 | $0.4250 | 1.68% |
| 1971-02-04 | $0.4250 | 1.37% |
| 1971-05-05 | $0.4250 | 1.47% |
| 1971-08-04 | $0.4250 | 1.54% |
| 1971-11-04 | $0.4250 | 1.53% |
| 1972-02-04 | $0.4450 | 1.45% |
| 1972-05-04 | $0.4350 | 1.53% |
| 1972-08-04 | $0.4350 | 1.56% |
| 1972-11-03 | $0.4500 | 1.51% |
| 1973-02-05 | $0.4500 | 1.54% |
| 1973-05-04 | $0.4500 | 1.70% |
| 1973-08-06 | $0.4750 | 1.83% |
| 1973-11-02 | $0.4750 | 1.80% |
| 1974-02-04 | $0.4750 | 1.84% |
| 1974-05-06 | $0.5000 | 2.19% |
| 1974-11-04 | $0.5000 | 3.01% |
| 1975-02-04 | $0.5000 | 2.74% |
| 1975-05-05 | $0.5000 | 2.92% |
| 1975-08-05 | $0.5000 | 2.50% |
| 1975-11-03 | $0.5000 | 2.40% |
| 1976-02-03 | $0.5000 | 2.15% |
| 1976-05-04 | $0.5000 | 2.22% |
| 1976-08-04 | $0.5000 | 2.20% |
| 1976-11-04 | $0.5150 | 2.17% |
| 1977-02-04 | $0.5150 | 2.04% |
| 1977-05-04 | $0.5150 | 2.06% |
| 1977-08-04 | $0.5150 | 2.03% |
| 1977-11-03 | $0.5300 | 2.17% |
| 1978-02-06 | $0.5300 | 2.21% |
| 1978-05-04 | $0.5300 | 2.27% |
| 1978-08-04 | $0.5300 | 2.16% |
| 1978-10-31 | $0.5450 | 2.42% |
| 1979-02-05 | $0.5450 | 2.38% |
| 1979-05-04 | $0.5450 | 2.53% |
| 1979-08-06 | $0.5450 | 2.49% |
| 1979-11-02 | $0.5550 | 2.94% |
| 1980-02-05 | $0.5550 | 2.98% |
| 1980-05-05 | $0.5550 | 2.96% |
| 1980-08-05 | $0.5550 | 2.94% |
| 1981-02-04 | $0.5650 | 3.35% |
| 1981-05-05 | $0.5650 | 3.53% |
| 1981-08-04 | $0.5650 | 3.30% |
| 1981-11-04 | $0.5650 | 3.32% |
| 1982-02-04 | $0.5650 | 3.40% |
| 1982-05-04 | $0.5650 | 3.21% |
| 1982-08-04 | $0.5650 | 3.32% |
| 1982-11-04 | $0.5650 | 2.90% |
| 1983-02-04 | $0.5650 | 2.95% |
| 1983-05-04 | $0.5650 | 2.90% |
| 1983-08-04 | $0.5650 | 2.99% |
| 1983-11-03 | $0.5650 | 2.92% |
| 1984-02-06 | $0.5650 | 3.07% |
| 1984-05-04 | $0.5650 | 3.42% |
| 1984-08-06 | $0.5650 | 3.07% |
| 1984-11-02 | $0.5650 | 2.77% |
| 1985-02-05 | $0.5650 | 2.61% |
| 1985-05-06 | $0.5650 | 2.61% |
| 1985-08-05 | $0.5650 | 2.43% |
| 1985-11-05 | $0.5650 | 2.48% |
| 1986-02-04 | $0.5650 | 2.20% |
| 1986-05-05 | $0.5650 | 2.13% |
| 1986-08-05 | $0.5650 | 1.93% |
| 1986-11-04 | $0.5650 | 1.88% |
| 1987-02-04 | $0.5650 | 1.81% |
| 1987-05-05 | $0.5650 | 2.02% |
| 1987-08-04 | $0.6450 | 2.38% |
| 1987-11-04 | $0.5650 | 2.10% |
| 1988-02-04 | $0.5650 | 1.94% |
| 1988-05-04 | $0.5650 | 2.07% |
| 1988-08-04 | $0.5920 | 2.07% |
| 1988-11-04 | $0.5920 | 2.10% |
| 1989-02-06 | $0.5800 | 2.13% |
| 1989-05-04 | $0.5800 | 2.19% |
| 1989-08-04 | $0.6000 | 1.97% |
| 1990-02-05 | $0.6000 | 1.94% |
| 1990-05-04 | $0.6000 | 2.05% |
| 1990-08-06 | $0.6000 | 2.03% |
| 1990-11-05 | $0.6000 | 2.07% |
| 1991-02-04 | $0.6000 | 2.18% |
| 1991-05-06 | $0.6000 | 2.02% |
| 1991-08-05 | $0.6000 | 2.00% |
| 1991-11-04 | $0.6000 | 1.90% |
| 1992-02-04 | $0.6000 | 1.88% |
| 1992-05-04 | $0.6000 | 1.88% |
| 1992-08-04 | $0.6000 | 1.73% |
| 1992-11-04 | $0.6000 | 1.85% |
| 1993-02-04 | $0.6000 | 1.72% |
| 1993-05-04 | $0.6000 | 1.61% |
| 1993-08-04 | $0.6000 | 1.57% |
| 1993-11-04 | $0.6000 | 1.63% |
| 1994-02-04 | $0.6000 | 1.67% |
| 1994-05-04 | $0.6000 | 1.85% |
| 1994-08-04 | $0.6000 | 1.90% |
| 1994-11-04 | $0.6000 | 1.88% |
| 1995-02-06 | $0.6000 | 1.68% |
| 1995-05-04 | $0.6000 | 1.84% |
| 1995-08-08 | $0.6000 | 1.71% |
| 1995-11-08 | $0.6000 | 1.57% |
| 1996-02-08 | $0.6000 | 1.36% |
| 1996-05-08 | $0.6000 | 1.51% |
| 1996-08-07 | $0.6000 | 1.41% |
| 1996-11-06 | $0.6000 | 1.42% |
| 1997-02-06 | $0.6000 | 1.46% |
| 1997-05-07 | $0.6000 | 1.42% |
| 1997-08-06 | $0.6000 | 1.35% |
| 1997-11-06 | $0.6000 | 1.26% |
| 1998-02-06 | $0.6000 | 1.21% |
| 1998-05-06 | $0.6000 | 1.27% |
| 1998-08-06 | $0.6000 | 1.37% |
| 1998-11-06 | $0.6000 | 1.19% |
| 1999-02-08 | $0.6000 | 1.40% |
| 1999-05-06 | $0.6000 | 1.43% |
| 1999-08-06 | $0.6000 | 1.64% |
| 1999-11-08 | $0.6000 | 1.71% |
| 2000-02-08 | $0.6000 | 1.78% |
| 2000-05-08 | $0.6000 | 1.73% |
| 2000-08-08 | $0.6000 | 1.71% |
| 2000-11-08 | $0.6000 | 1.47% |
| 2001-02-07 | $0.6000 | 1.35% |
| 2001-05-08 | $0.6000 | 1.24% |
| 2001-08-08 | $0.6000 | 1.32% |
| 2001-11-07 | $0.6000 | 1.36% |
| 2002-02-06 | $0.6000 | 1.45% |
| 2002-05-08 | $0.6000 | 1.29% |
| 2002-08-07 | $0.6000 | 1.86% |
| 2002-11-06 | $0.6000 | 2.14% |
| 2003-02-06 | $0.6000 | 2.65% |
| 2003-05-07 | $0.3500 | 1.36% |
| 2003-08-06 | $0.3500 | 1.27% |
| 2003-11-06 | $0.3500 | 1.26% |
| 2004-02-06 | $0.3500 | 1.06% |
| 2004-05-06 | $0.3500 | 1.13% |
| 2004-08-06 | $0.3500 | 1.09% |
| 2004-11-08 | $0.3500 | 1.02% |
| 2005-02-08 | $0.3500 | 0.99% |
| 2005-05-06 | $0.3500 | 0.99% |
| 2005-08-08 | $0.3500 | 0.92% |
| 2005-11-08 | $0.3700 | 1.00% |
| 2006-02-08 | $0.3700 | 1.03% |
| 2006-05-08 | $0.3700 | 1.09% |
| 2006-08-08 | $0.3700 | 1.01% |
| 2006-11-08 | $0.3900 | 0.94% |
| 2007-02-07 | $0.3900 | 0.87% |
| 2007-05-08 | $0.3900 | 0.77% |
| 2007-08-08 | $0.3900 | 0.82% |
| 2007-11-07 | $0.4100 | 0.86% |
| 2008-02-06 | $0.4100 | 0.94% |
| 2008-05-07 | $0.4100 | 0.93% |
| 2008-08-06 | $0.4100 | 1.03% |
| 2008-11-06 | $0.4100 | 1.29% |
| 2009-02-06 | $0.4100 | 1.22% |
| 2009-05-06 | $0.4100 | 1.54% |
| 2009-08-06 | $0.4100 | 1.33% |
| 2009-11-06 | $0.4100 | 1.31% |
| 2010-02-08 | $0.4100 | 1.22% |
| 2010-05-06 | $0.4200 | 1.26% |
| 2010-08-06 | $0.4200 | 1.15% |
| 2010-11-08 | $0.4600 | 1.22% |
| 2011-02-08 | $0.4600 | 1.28% |
| 2011-05-06 | $0.4600 | 1.25% |
| 2011-08-08 | $0.4600 | 1.27% |
| 2011-11-08 | $0.4700 | 1.18% |
| 2012-02-08 | $0.4700 | 1.18% |
| 2012-05-08 | $0.4700 | 1.22% |
| 2012-08-08 | $0.4700 | 1.12% |
| 2012-11-07 | $0.4700 | 1.08% |
| 2013-02-06 | $0.4700 | 1.05% |
| 2013-05-08 | $0.4900 | 0.96% |
| 2013-08-07 | $0.4900 | 1.07% |
| 2013-11-06 | $0.5000 | 1.07% |
| 2014-02-06 | $0.5000 | 1.04% |
| 2014-05-07 | $0.5000 | 0.95% |
| 2014-08-06 | $0.5000 | 0.98% |
| 2014-11-06 | $0.5300 | 0.89% |
| 2015-02-06 | $0.5300 | 0.85% |
| 2015-05-06 | $0.5300 | 0.95% |
| 2015-08-06 | $0.5300 | 0.94% |
| 2015-11-06 | $0.5600 | 0.99% |
| 2016-02-08 | $0.5600 | 0.89% |
| 2016-05-06 | $0.5600 | 0.86% |
| 2016-08-08 | $0.5600 | 0.83% |
| 2016-11-08 | $0.5900 | 0.93% |
| 2017-02-08 | $0.5900 | 0.92% |
| 2017-05-08 | $0.5900 | 0.86% |
| 2017-08-08 | $0.5900 | 0.83% |
| 2017-11-09 | $0.6200 | 0.82% |
| 2018-02-08 | $0.6200 | 0.96% |
| 2018-05-09 | $0.6200 | 0.92% |
| 2018-08-09 | $0.6200 | 0.87% |
| 2018-11-08 | $0.6700 | 0.89% |
| 2019-02-07 | $0.6700 | 0.85% |
| 2019-05-09 | $0.6700 | 0.80% |
| 2019-08-08 | $0.6700 | 0.75% |
| 2019-11-07 | $0.7000 | 0.76% |
| 2020-02-07 | $0.7000 | 0.68% |
| 2020-05-07 | $0.7000 | 0.89% |
| 2020-08-07 | $0.7000 | 0.82% |
| 2020-11-09 | $0.7400 | 0.81% |
| 2021-02-09 | $0.7400 | 0.91% |
| 2021-05-07 | $0.7400 | 0.84% |
| 2021-08-09 | $0.7400 | 0.83% |
| 2021-11-09 | $0.7800 | 0.93% |
| 2022-02-09 | $0.7800 | 0.86% |
| 2022-05-09 | $0.7800 | 0.78% |
| 2022-08-09 | $0.7800 | 0.78% |
| 2022-11-09 | $0.8300 | 0.93% |
| 2023-02-09 | $0.8300 | 0.92% |
| 2023-05-09 | $0.8300 | 0.90% |
| 2023-08-09 | $0.8300 | 1.03% |
| 2023-11-09 | $0.8800 | 1.13% |
| 2024-02-08 | $0.8800 | 1.14% |
| 2024-05-09 | $0.8800 | 0.97% |
| 2024-08-09 | $0.8800 | 0.90% |
| 2024-11-08 | $0.9300 | 0.97% |
| 2025-02-10 | $0.9300 | 0.93% |
| 2025-05-09 | $0.9300 | 0.88% |
| 2025-08-08 | $0.9300 | 0.82% |
| 2025-11-10 | $0.9500 | 0.78% |
| 2026-02-10 | $0.9500 | 0.78% |
| Total | 222 payments |
Portfolio Dividend Returns
Based on $10,000 initial investment, 20% tax rate, 0.2% transaction cost. Showing 2021-04-14 to 2026-04-14. Change
| Date | Total Yield | Tax | Trans. Cost | Shares Bought |
|---|---|---|---|---|
| 2021-05-07 | $84.99 | $17.00 | $0.14 | 0.7782 |
| 2021-08-09 | $85.56 | $17.11 | $0.14 | 0.7697 |
| 2021-11-09 | $90.79 | $18.16 | $0.15 | 0.8729 |
| 2022-02-09 | $91.47 | $18.29 | $0.15 | 0.8171 |
| 2022-05-09 | $92.11 | $18.42 | $0.15 | 0.7377 |
| 2022-08-09 | $92.68 | $18.54 | $0.15 | 0.7358 |
| 2022-11-09 | $99.24 | $19.85 | $0.16 | 0.9022 |
| 2023-02-09 | $99.98 | $20.00 | $0.16 | 0.9022 |
| 2023-05-09 | $100.73 | $20.15 | $0.16 | 0.8828 |
| 2023-08-09 | $101.47 | $20.29 | $0.16 | 1.0037 |
| 2023-11-09 | $108.46 | $21.69 | $0.17 | 1.1208 |
| 2024-02-08 | $109.45 | $21.89 | $0.18 | 1.1507 |
| 2024-05-09 | $110.46 | $22.09 | $0.18 | 0.9697 |
| 2024-08-09 | $111.31 | $22.26 | $0.18 | 0.9112 |
| 2024-11-08 | $118.49 | $23.70 | $0.19 | 0.9813 |
| 2025-02-10 | $119.40 | $23.88 | $0.19 | 0.9454 |
| 2025-05-09 | $120.28 | $24.06 | $0.19 | 0.9174 |
| 2025-08-08 | $121.13 | $24.23 | $0.19 | 0.8597 |
| 2025-11-10 | $124.55 | $24.91 | $0.20 | 0.8114 |
| 2026-02-10 | $125.32 | $25.06 | $0.20 | 0.8254 |
| Total | $2107.89 | $421.58 | $3.37 | 17.8953 |
All calculations use split-adjusted closing prices. Dividends are reinvested on the ex-dividend date at that day's closing price.
For each rolling window, returns are calculated at every possible starting point:
return = (value[i] ÷ value[i − windowSize] − 1) × 100
- Windows
- 1-month = 21 trading days, 1-year = 252 trading days, 3-year = 756 trading days.
- Statistics
- Average: arithmetic mean. Median: middle value when sorted. Best / Worst: max and min. % Positive: share of windows with return > 0.
The series is segmented by calendar year:
return = (endValue ÷ startValue − 1) × 100
startValue is the last value of the prior year (or the first value for the initial year). Partial first/last years are flagged. Dividends, taxes, and transaction costs are scaled proportionally to the initial investment.