If only we could return to 1984 and put 100k in. The figures below are minus fees and ignore dividend income. We assume a 20 year holding period with 100k invested. For ease no reinvestment is assumed.
Exit Date FTSE100 at start FTSE100 at end 20 year return £100k invested
01/01/2004 1000.00 4476.87 347.7% £ 447,687.00
02/01/2004 1060.30 4381.37 313.2% £ 413,219.84
03/01/2004 1046.10 4537 333.7% £ 433,706.15
04/01/2004 1108.10 4410.71 298.0% £ 398,042.60
05/01/2004 1136.80 4489.69 294.9% £ 394,941.06
06/01/2004 1026.80 4422.68 330.7% £ 430,724.58
07/01/2004 1041.30 4424.72 324.9% £ 424,922.69
08/01/2004 1006.20 4415.73 338.9% £ 438,852.12
09/01/2004 1105.30 4502.05 307.3% £ 407,314.76
10/01/2004 1127.70 4659.65 313.2% £ 413,199.43
11/01/2004 1158.40 4673.79 303.5% £ 403,469.44
12/01/2004 1191.70 4735.68 297.4% £ 397,388.60
01/01/2005 1232.20 4814.3 290.7% £ 390,707.68
02/01/2005 1272.60 4906.21 285.5% £ 385,526.48
03/01/2005 1250.80 5000.47 299.8% £ 399,781.74
04/01/2005 1278.30 4914.03 284.4% £ 384,419.15
05/01/2005 1301.50 4801.68 268.9% £ 368,934.31
06/01/2005 1324.60 5011.04 278.3% £ 378,305.90
07/01/2005 1246.80 5161.01 313.9% £ 413,940.49
08/01/2005 1287.20 5290.85 311.0% £ 411,035.58
09/01/2005 1340.30 5328.51 297.6% £ 397,560.99
10/01/2005 1296.00 5501.55 324.5% £ 424,502.31
11/01/2005 1379.00 5344.33 287.6% £ 387,551.12
12/01/2005 1418.50 5486.12 286.8% £ 386,755.02
01/01/2006 1412.60 5618.76 297.8% £ 397,760.16
02/01/2006 1425.10 5801.63 307.1% £ 407,103.36
03/01/2006 1534.90 5844.07 280.7% £ 380,745.98
04/01/2006 1684.00 6024.28 257.7% £ 357,736.34
05/01/2006 1640.10 6023.14 267.2% £ 367,242.24
06/01/2006 1596.50 5749.69 260.1% £ 360,143.44
07/01/2006 1660.80 5884.44 254.3% £ 354,313.58
08/01/2006 1561.80 5880.84 276.5% £ 376,542.45
09/01/2006 1672.80 5949.15 255.6% £ 355,640.24
10/01/2006 1578.30 5957.83 277.5% £ 377,484.00
11/01/2006 1639.20 6149.62 275.2% £ 375,159.83
12/01/2006 1617.80 6021.54 272.2% £ 372,205.46
01/01/2007 1679.00 6220.81 270.5% £ 370,506.85
02/01/2007 1832.80 6282.23 242.8% £ 342,766.80
03/01/2007 1983.10 6116.04 208.4% £ 308,408.05
04/01/2007 1973.10 6315.53 220.1% £ 320,081.60
05/01/2007 2068.50 6419.61 210.4% £ 310,350.98
06/01/2007 2228.20 6676.66 199.6% £ 299,643.66
07/01/2007 2269.80 6590.55 190.4% £ 290,358.18
08/01/2007 2334.30 6250.57 167.8% £ 267,770.64
09/01/2007 2272.80 6315.22 177.9% £ 277,860.79
10/01/2007 2373.80 6506.25 174.1% £ 274,085.85
11/01/2007 1723.70 6586.08 282.1% £ 382,089.69
12/01/2007 1578.50 6386.57 304.6% £ 404,597.40
01/01/2008 1712.70 6456.91 277.0% £ 377,001.81
02/01/2008 1776.90 6029.18 239.3% £ 339,308.91
03/01/2008 1781.90 5818.62 226.5% £ 326,540.21
04/01/2008 1742.50 5852.58 235.9% £ 335,872.60
05/01/2008 1802.20 6087.25 237.8% £ 337,767.73
06/01/2008 1805.70 6007.61 232.7% £ 332,702.55
07/01/2008 1858.20 5479.93 194.9% £ 294,905.28
08/01/2008 1862.20 5354.67 187.5% £ 287,545.38
09/01/2008 1730.50 5602.82 223.8% £ 323,768.85
10/01/2008 1802.60 4959.59 175.1% £ 275,135.36
11/01/2008 1857.80 4443.28 139.2% £ 239,168.91
12/01/2008 1778.70 4065.49 128.6% £ 228,565.24
01/01/2009 1793.10 4434.17 147.3% £ 247,290.73
02/01/2009 2039.70 4077.78 99.9% £ 199,920.58
03/01/2009 2021.30 3625.83 79.4% £ 179,381.09
04/01/2009 2079.60 3955.61 90.2% £ 190,210.14
05/01/2009 2118.00 4243.22 100.3% £ 200,340.89
06/01/2009 2103.40 4506.19 114.2% £ 214,233.62
07/01/2009 2165.60 4340.71 100.4% £ 200,439.14
08/01/2009 2292.30 4682.46 104.3% £ 204,269.07
09/01/2009 2407.50 4819.7 100.2% £ 200,195.22
10/01/2009 2289.20 5047.81 120.5% £ 220,505.42
11/01/2009 2160.10 5104.5 136.3% £ 236,308.50
12/01/2009 2311.10 5312.17 129.9% £ 229,854.61
01/01/2010 2422.70 5412.88 123.4% £ 223,423.45
02/01/2010 2345.80 5247.41 123.7% £ 223,693.84
03/01/2010 2238.40 5405.94 141.5% £ 241,509.11
04/01/2010 2221.60 5744.89 158.6% £ 258,592.46
05/01/2010 2117.90 5553.29 162.2% £ 262,207.38
06/01/2010 2371.40 5163.3 117.7% £ 217,732.14
07/01/2010 2372.00 4805.75 102.6% £ 202,603.29
08/01/2010 2339.00 5397.11 130.7% £ 230,744.34
09/01/2010 2166.60 5366.41 147.7% £ 247,688.08
10/01/2010 2030.80 5592.9 175.4% £ 275,403.78
11/01/2010 2028.00 5694.62 180.8% £ 280,799.80
12/01/2010 2162.70 5642.5 160.9% £ 260,900.73
01/01/2011 2143.50 5899.94 175.2% £ 275,247.96
02/01/2011 2165.70 5957.82 175.1% £ 275,099.04
03/01/2011 2386.90 5935.76 148.7% £ 248,680.72
04/01/2011 2456.50 6009.92 144.7% £ 244,653.78
05/01/2011 2508.40 6069.9 142.0% £ 241,982.94
06/01/2011 2515.80 5928.61 135.7% £ 235,655.06
07/01/2011 2443.60 5989.76 145.1% £ 245,120.31
08/01/2011 2591.70 5774.43 122.8% £ 222,804.72
09/01/2011 2679.60 5418.65 102.2% £ 202,218.61
10/01/2011 2645.60 5075.5 91.8% £ 191,846.84
11/01/2011 2549.50 5421.57 112.7% £ 212,652.28
12/01/2011 2414.90 5489.34 127.3% £ 227,311.28
01/01/2012 2493.10 5572.28 123.5% £ 223,508.08
02/01/2012 2560.20 5790.72 126.2% £ 226,182.33
03/01/2012 2554.30 5931.25 132.2% £ 232,206.48
04/01/2012 2408.60 5874.89 143.9% £ 243,913.06
05/01/2012 2659.80 5812.23 118.5% £ 218,521.32
06/01/2012 2697.60 5260.19 95.0% £ 194,995.18
07/01/2012 2493.90 5640.64 126.2% £ 226,177.47
08/01/2012 2420.20 5712.82 136.0% £ 236,047.43
09/01/2012 2298.40 5758.41 150.5% £ 250,539.94
10/01/2012 2572.30 5820.45 126.3% £ 226,274.15
11/01/2012 2687.80 5861.92 118.1% £ 218,093.61
12/01/2012 2792.00 5871.24 110.3% £ 210,287.97
01/01/2013 2846.50 5897.81 107.2% £ 207,195.15
02/01/2013 2851.60 6347.24 122.6% £ 222,585.22
03/01/2013 2882.60 6378.6 121.3% £ 221,279.40
04/01/2013 2878.40 6411.74 122.8% £ 222,753.61
05/01/2013 2813.10 6451.29 129.3% £ 229,330.28
06/01/2013 2849.20 6525.12 129.0% £ 229,015.86
07/01/2013 2888.80 6307.78 118.4% £ 218,352.95
08/01/2013 2941.70 6681.98 127.1% £ 227,146.89
09/01/2013 3085.10 6506.19 110.9% £ 210,890.73
10/01/2013 3039.30 6460.01 112.5% £ 212,549.27
11/01/2013 3164.40 6734.74 112.8% £ 212,828.34
12/01/2013 3233.20 6595.33 104.0% £ 203,987.69
01/01/2014 3418.40 6749.09 97.4% £ 197,434.18
02/01/2014 3481.50 6465.66 85.7% £ 185,714.78
03/01/2014 3270.60 6708.35 105.1% £ 205,110.68
04/01/2014 3086.40 6652.61 115.5% £ 215,545.94
05/01/2014 3125.30 6808.87 117.9% £ 217,862.93
06/01/2014 2931.90 6864.1 134.1% £ 234,117.81
07/01/2014 2936.40 6802.92 131.7% £ 231,675.52
08/01/2014 3097.40 6679.18 115.6% £ 215,638.28
09/01/2014 3216.50 6825.31 112.2% £ 212,196.80
10/01/2014 2983.50 6557.52 119.8% £ 219,792.86
11/01/2014 3096.30 6487.97 109.5% £ 209,539.45
12/01/2014 3039.60 6656.37 119.0% £ 218,988.35
01/01/2015 3065.50 6566.09 114.2% £ 214,193.12
02/01/2015 3017.30 6782.55 124.8% £ 224,788.72
03/01/2015 3041.20 6940.64 128.2% £ 228,220.44
04/01/2015 3143.10 6809.5 116.6% £ 216,649.17
05/01/2015 3220.40 6985.95 116.9% £ 216,928.02
06/01/2015 3340.60 6953.58 108.2% £ 208,153.63
07/01/2015 3323.70 6608.59 98.8% £ 198,832.33
08/01/2015 3449.90 6688.62 93.9% £ 193,878.66
09/01/2015 3509.40 6058.54 72.6% £ 172,637.49
10/01/2015 3520.20 6072.47 72.5% £ 172,503.55
11/01/2015 3518.70 6361.8 80.8% £ 180,799.73
12/01/2015 3680.40 6395.65 73.8% £ 173,775.95
01/01/2016 3689.30 6242.32 69.2% £ 169,200.66
02/01/2016 3752.80 6060.1 61.5% £ 161,482.09
03/01/2016 3752.70 6152.88 64.0% £ 163,958.75
04/01/2016 3718.40 6146.05 65.3% £ 165,287.49
05/01/2016 3806.00 6241.89 64.0% £ 164,001.31
06/01/2016 3739.20 6191.93 65.6% £ 165,595.05
07/01/2016 3725.60 6577.83 76.6% £ 176,557.60
08/01/2016 3734.40 6693.95 79.3% £ 179,251.02
09/01/2016 3884.40 6745.97 73.7% £ 173,668.26
10/01/2016 3992.20 6983.52 74.9% £ 174,929.11
11/01/2016 3948.50 6917.14 75.2% £ 175,183.99
12/01/2016 4038.50 6752.93 67.2% £ 167,213.82
01/01/2017 4118.50 7142.83 73.4% £ 173,432.80
Bloody hell where did you get that from?