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在2008金融海嘯高點單筆投資及定期定額投資0050成效比較

定期定額投資法理論上在股市下跌時會比單筆投資安全，因為向下攤平成本的效果，但是定期定額投資失去了單筆投資的複利效果，以下是從2007年10月11日0050的最高點每股71.9元開始投資。計算方式如下：

  • 計算時間區分1年、5年、10年及12年。
  • 0050股利會在除權息日全數買進0050。
  • 定期定額為每月投入1萬元台幣。
  • 單筆投資金額與定期定額投資金額總額相同。
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投資1年成果比較

從2007年10月11日0050的最高點每股71.9元開始投資1年，總共投資120,000元。
  • 定期定額1年後現值為79,358元，報酬率為-33.87%。
  • 單筆投資1年後現值為67,217元，報酬率為-43.99%。

定期定額投資成果計算

日期 價格 投入金額 總單位數 總現值
2007/10/11 71.9 10,000 139.082 10,000
2007/10/24 67.7 347.705 144.2179675 9,764
2007/11/12 63.6 10,000 301.4506719 19,172
2007/12/11 62.35 10,000 461.8355957 28,795
2008/1/11 57.65 10,000 635.2961335 36,625
2008/02/12 54.95 10,000 817.2797549 44,910
2008/03/11 60.1 10,000 983.669106 59,119
2008/04/11 63.5 10,000 1141.149421 72,463
2008/05/12 62.7 10,000 1300.639054 81,550
2008/06/11 59.9 10,000 1467.583962 87,908
2008/07/11 52.9 10,000 1656.619879 87,635
2008/08/11 55.6 10,000 1836.475994 102,108
2008/09/11 48.37 10,000 2043.215709 98,830
2008/10/13 38.84 0 2043.215709 79,358

單筆投資成果計算

日期 價格 投入金額 總單位數 總現值
2007/10/11 71.9 120,000 139.082 10,000
2007/10/24 67.7 4172.462 1730.616337 117,163
2008/10/13 38.84 0 1730.616337 67,217

投資5年成果比較

從2007年10月11日0050的最高點每股71.9元開始投資1年，總共投資600,000元。
  • 定期定額5年後現值為672,846元，報酬率為12.14%。
  • 單筆投資5年後現值為537,882元，報酬率為-10.35%。

定期定額投資成果計算

日期 價格 投入金額 總單位數 總現值
2007/10/11 71.9 10000 139.082 10,000
2007/10/24 67.7 347.705 144.2179675 9,764
2007/11/12 63.6 10000 301.4506719 19,172
2007/12/11 62.35 10000 461.8355957 28,795
2008/1/11 57.65 10000 635.2961335 36,625
2008/02/12 54.95 10000 817.2797549 44,910
2008/03/11 60.1 10000 983.669106 59,119
2008/04/11 63.5 10000 1141.149421 72,463
2008/05/12 62.7 10000 1300.639054 81,550
2008/06/11 59.9 10000 1467.583962 87,908
2008/07/11 52.9 10000 1656.619879 87,635
2008/08/11 55.6 10000 1836.475994 102,108
2008/09/11 48.37 10000 2043.215709 98,830
2008/10/13 38.84 10000 2300.682238 89,358
2008/10/24 32.34 4601.364477 2442.963144 79,005
2008/11/11 33.46 10000 2741.827459 91,742
2008/12/11 33.8 10000 3037.685447 102,674
2009/01/10 32.01 10000 3350.087822 107,236
2009/02/11 33.25 10000 3650.839701 121,390
2009/03/11 34.25 10000 3942.810504 135,041
2009/04/10 39.97 10000 4192.998145 167,594
2009/05/11 46.2 10000 4409.448361 203,717
2009/06/11 45.25 10000 4630.442837 209,528
2009/07/10 46.78 10000 4844.209403 226,612
2009/08/11 48.42 10000 5050.735632 244,557
2009/09/11 52.5 10000 5241.211823 275,164
2009/10/12 53.6 10000 5427.778987 290,929
2009/10/23 53.25 5427.778987 5529.709109 294,457
2009/11/11 53.85 10000 5715.41013 307,775
2009/12/11 53.85 10000 5901.111151 317,775
2010/01/11 57.9 10000 6073.822723 351,674
2010/02/10 52.1 10000 6265.761303 326,446
2010/03/11 53.65 10000 6452.154593 346,158
2010/04/12 55.45 10000 6632.497244 367,772
2010/05/11 52.2 10000 6824.068125 356,216
2010/06/11 49.62 10000 7025.599765 348,610
2010/07/12 52.3 10000 7216.804354 377,439
2010/08/11 54.7 10000 7399.619711 404,759
2010/09/10 55.25 10000 7580.615186 418,829
2010/10/11 56.95 10000 7756.207811 441,716
2010/10/25 56.1 17063.65718 8060.372823 452,187
2010/11/11 57.5 10000 8234.285867 473,471
2010/12/10 59.3 10000 8402.919931 498,293
2011/01/11 60.85 10000 8567.258468 521,318
2011/02/11 58.9 10000 8737.037755 514,612
2011/03/11 58.85 10000 8906.961289 524,175
2011/04/11 61.1 10000 9070.627411 554,215
2011/05/11 62.05 10000 9231.787765 572,832
2011/06/10 60.55 10000 9396.940531 568,985
2011/07/11 59.65 10000 9564.585125 570,528
2011/08/11 54.1 10000 9749.428008 527,444
2011/09/09 54.15 10000 9934.100215 537,932
2011/10/11 53 10000 10122.77946 536,507
2011/10/26 52.15 19739.41995 10501.29183 547,642
2011/10/11 53 10000 10689.97107 566,568
2011/12/12 48.8 10000 10894.88911 531,671
2012/01/11 50.65 10000 11092.32247 561,826
2012/02/10 53.95 10000 11277.67928 608,431
2012/03/12 54.35 10000 11461.67192 622,942
2012/04/11 53.3 10000 11649.28919 620,907
2012/05/11 51.15 10000 11844.79261 605,861
2012/06/11 48.99 10000 12048.9159 590,276
2012/07/11 50.55 10000 12246.73983 619,073
2012/08/10 52.8 10000 12436.13377 656,628
2012/09/11 53.3 10000 12623.75103 672,846
2012/10/11 53.3 0 12623.75103 672,846

單筆投資成果計算

日期 價格 投入金額 總單位數 總現值
2007/10/11 71.9 600000 8344.923505 600000
2007/10/24 67.7 20862.30876 8653.081685 585,814
2008/10/24 32.34 17306.16337 9188.213514 297,147
2009/10/23 53.25 9188.213514 9360.762125 498,461
2010/10/25 56.1 20593.67667 9727.850835 545,732
2011/10/26 52.15 18969.30913 10091.59598 526,277
2012/10/11 53.3 0 10091.59598 537,882

投資10年成果比較

從2007年10月11日0050的最高點每股71.9元開始投資1年，總共投資1,200,000元。
  • 定期定額10年後現值為2,036,871元，報酬率為69.74%。
  • 單筆投資10年後現值為1,925,460元，報酬率為60.46%。

定期定額投資成果計算

日期價格投入金額總單位數總現值
2007/10/1171.910000139.08210,000
2007/10/2467.7347.705144.21796759,764
2007/11/1263.610000301.450671919,172
2007/12/1162.3510000461.835595728,795
2008/1/1157.6510000635.296133536,625
2008/02/1254.9510000817.279754944,910
2008/03/1160.110000983.66910659,119
2008/04/1163.5100001141.14942172,463
2008/05/1262.7100001300.63905481,550
2008/06/1159.9100001467.58396287,908
2008/07/1152.9100001656.61987987,635
2008/08/1155.6100001836.475994102,108
2008/09/1148.37100002043.21570998,830
2008/10/1338.84100002300.68223889,358
2008/10/2432.344601.3644772442.96314479,005
2008/11/1133.46100002741.82745991,742
2008/12/1133.8100003037.685447102,674
2009/01/1032.01100003350.087822107,236
2009/02/1133.25100003650.839701121,390
2009/03/1134.25100003942.810504135,041
2009/04/1039.97100004192.998145167,594
2009/05/1146.2100004409.448361203,717
2009/06/1145.25100004630.442837209,528
2009/07/1046.78100004844.209403226,612
2009/08/1148.42100005050.735632244,557
2009/09/1152.5100005241.211823275,164
2009/10/1253.6100005427.778987290,929
2009/10/2353.255427.7789875529.709109294,457
2009/11/1153.85100005715.41013307,775
2009/12/1153.85100005901.111151317,775
2010/01/1157.9100006073.822723351,674
2010/02/1052.1100006265.761303326,446
2010/03/1153.65100006452.154593346,158
2010/04/1255.45100006632.497244367,772
2010/05/1152.2100006824.068125356,216
2010/06/1149.62100007025.599765348,610
2010/07/1252.3100007216.804354377,439
2010/08/1154.7100007399.619711404,759
2010/09/1055.25100007580.615186418,829
2010/10/1156.95100007756.207811441,716
2010/10/2556.117063.657188060.372823452,187
2010/11/1157.5100008234.285867473,471
2010/12/1059.3100008402.919931498,293
2011/01/1160.85100008567.258468521,318
2011/02/1158.9100008737.037755514,612
2011/03/1158.85100008906.961289524,175
2011/04/1161.1100009070.627411554,215
2011/05/1162.05100009231.787765572,832
2011/06/1060.55100009396.940531568,985
2011/07/1159.65100009564.585125570,528
2011/08/1154.1100009749.428008527,444
2011/09/0954.15100009934.100215537,932
2011/10/11531000010122.77946536,507
2011/10/2652.1519739.4199510501.29183547,642
2011/10/11531000010689.97107566,568
2011/12/1248.81000010894.88911531,671
2012/01/1150.651000011092.32247561,826
2012/02/1053.951000011277.67928608,431
2012/03/1254.351000011461.67192622,942
2012/04/1153.31000011649.28919620,907
2012/05/1151.151000011844.79261605,861
2012/06/1148.991000012048.9159590,276
2012/07/1150.551000012246.73983619,073
2012/08/1052.81000012436.13377656,628
2012/09/1153.31000012623.75103672,846
2012/10/1153.31000012811.36829682,846
2012/10/245123701.0313413276.0944677,081
2012/11/1250.91000013472.55805685,753
2012/12/1153.651000013658.95134732,803
2013/01/1154.451000013842.60607753,730
2013/02/0655.41000014023.11149776,880
2013/03/1155.91000014202.00236793,892
2013/04/1154.351000014385.995781,879
2013/05/1057.91000014558.70658842,949
2013/06/1156.351000014736.16887830,383
2013/07/1157.21000014910.99404852,909
2013/08/12551000015092.81222830,105
2013/09/1157.51000015266.72527877,837
2013/10/1158.451000015437.81166902,340
2013/10/2457.5520841.0457515799.94973909,287
2013/11/1156.31000015977.56962899,537
2013/12/1157.851000016150.43047934,302
2014/01/1057.551000016324.19242939,457
2014/02/1156.951000016499.78504939,663
2014/03/1159.351000016668.27704989,262
2014/04/1161.151000016831.809341,029,265
2014/05/1261.151000016995.341631,039,265
2014/06/1164.151000017151.226281,100,251
2014/07/1168.31000017297.639161,181,429
2014/08/1166.051000017449.039621,152,509
2014/09/1168.41000017595.238451,203,514
2014/10/13641000017751.488451,136,095
2014/10/2463.0527514.807118187.885071,146,746
2014/11/1165.951000018339.515091,209,491
2014/12/1165.251000018492.77181,206,653
2015/01/1265.751000018644.863051,225,900
2015/02/11691000018789.790591,296,496
2015/03/1169.051000018934.613181,307,435
2015/04/1069.651000019078.18821,328,796
2015/05/1170.851000019219.331461,361,690
2015/06/1168.851000019364.574741,333,251
2015/07/0967.11000019513.606041,309,363
2015/08/1164.551000019668.524711,269,603
2015/09/1163.51000019826.005021,258,951
2015/10/1265.551000019978.560321,309,595
2015/10/2664.5539957.1206520597.570711,329,573
2015/11/1162.151000020758.471761,290,139
2015/12/1159.851000020925.556141,252,395
2016/01/1156.551000021102.39081,193,340
2016/02/15591000021271.882321,255,041
2016/03/1163.551000021429.238731,361,828
2016/04/11631000021587.968891,360,042
2016/05/1159.851000021755.053271,302,040
2016/06/1363.751000021911.916021,396,885
2016/07/11671000022061.169751,478,098
2016/07/2869.0518751.9942922332.740991,542,076
2016/08/1169.951000022475.700251,572,175
2016/09/1069.41000022619.792471,569,814
2016/10/1171.451000022759.750481,626,184
2016/11/1170.051000022902.505651,604,321
2016/12/1272.851000023039.774011,678,448
2017/01/1172.41000023177.895561,678,080
2017/02/1072.81000023315.25821,697,351
2017/03/10721000023454.147091,688,699
2017/04/1173.91000023589.465081,743,261
2017/05/1176.51000023720.184041,814,594
2017/06/1277.151000023849.801671,840,012
2017/07/1181.551000023972.425821,954,951
2017/07/3181.3516780.6980824178.703611,966,938
2017/08/1181.251000024301.780531,974,520
2017/09/1182.551000024422.919242,016,112
2017/10/1183.4024422.919242,036,871

單筆投資成果計算

日期價格投入金額總單位數總現值
2007/10/1171.9120000016689.847011200000
2007/10/2467.741724.6175217306.163371,171,627
2008/10/2432.3434612.3267418376.42703594,294
2009/10/2353.2518376.4270318721.52425996,921
2010/10/2556.141187.3533519455.701671,091,465
2011/10/2652.1537938.6182620183.191951,052,553
2012/10/245137338.9051120915.327351,066,682
2013/10/2457.5528235.6919221405.956231,231,913
2014/10/2463.0533179.2321521932.193061,382,825
2015/10/2664.5543864.3861122611.734281,459,587
2016/07/2869.0519219.9741422890.082931,580,560
2017/07/3181.3516023.0580523087.047381,878,131
2017/10/1183.4023087.047381,925,460

投資12年成果比較

從2007年10月11日0050的最高點每股71.9元開始投資1年，總共投資1,440,000元。
  • 定期定額12年後現值為2,516,283元，報酬率為74.74%。
  • 單筆投資12年後現值為2,556,090元，報酬率為77.51%。

定期定額投資成果計算

日期價格投入金額總單位數總現值
2007/10/1171.910000139.08210,000
2007/10/2467.7347.705144.21796759,764
2007/11/1263.610000301.450671919,172
2007/12/1162.3510000461.835595728,795
2008/1/1157.6510000635.296133536,625
2008/02/1254.9510000817.279754944,910
2008/03/1160.110000983.66910659,119
2008/04/1163.5100001141.14942172,463
2008/05/1262.7100001300.63905481,550
2008/06/1159.9100001467.58396287,908
2008/07/1152.9100001656.61987987,635
2008/08/1155.6100001836.475994102,108
2008/09/1148.37100002043.21570998,830
2008/10/1338.84100002300.68223889,358
2008/10/2432.344601.3644772442.96314479,005
2008/11/1133.46100002741.82745991,742
2008/12/1133.8100003037.685447102,674
2009/01/1032.01100003350.087822107,236
2009/02/1133.25100003650.839701121,390
2009/03/1134.25100003942.810504135,041
2009/04/1039.97100004192.998145167,594
2009/05/1146.2100004409.448361203,717
2009/06/1145.25100004630.442837209,528
2009/07/1046.78100004844.209403226,612
2009/08/1148.42100005050.735632244,557
2009/09/1152.5100005241.211823275,164
2009/10/1253.6100005427.778987290,929
2009/10/2353.255427.7789875529.709109294,457
2009/11/1153.85100005715.41013307,775
2009/12/1153.85100005901.111151317,775
2010/01/1157.9100006073.822723351,674
2010/02/1052.1100006265.761303326,446
2010/03/1153.65100006452.154593346,158
2010/04/1255.45100006632.497244367,772
2010/05/1152.2100006824.068125356,216
2010/06/1149.62100007025.599765348,610
2010/07/1252.3100007216.804354377,439
2010/08/1154.7100007399.619711404,759
2010/09/1055.25100007580.615186418,829
2010/10/1156.95100007756.207811441,716
2010/10/2556.117063.657188060.372823452,187
2010/11/1157.5100008234.285867473,471
2010/12/1059.3100008402.919931498,293
2011/01/1160.85100008567.258468521,318
2011/02/1158.9100008737.037755514,612
2011/03/1158.85100008906.961289524,175
2011/04/1161.1100009070.627411554,215
2011/05/1162.05100009231.787765572,832
2011/06/1060.55100009396.940531568,985
2011/07/1159.65100009564.585125570,528
2011/08/1154.1100009749.428008527,444
2011/09/0954.15100009934.100215537,932
2011/10/11531000010122.77946536,507
2011/10/2652.1519739.4199510501.29183547,642
2011/10/11531000010689.97107566,568
2011/12/1248.81000010894.88911531,671
2012/01/1150.651000011092.32247561,826
2012/02/1053.951000011277.67928608,431
2012/03/1254.351000011461.67192622,942
2012/04/1153.31000011649.28919620,907
2012/05/1151.151000011844.79261605,861
2012/06/1148.991000012048.9159590,276
2012/07/1150.551000012246.73983619,073
2012/08/1052.81000012436.13377656,628
2012/09/1153.31000012623.75103672,846
2012/10/1153.31000012811.36829682,846
2012/10/245123701.0313413276.0944677,081
2012/11/1250.91000013472.55805685,753
2012/12/1153.651000013658.95134732,803
2013/01/1154.451000013842.60607753,730
2013/02/0655.41000014023.11149776,880
2013/03/1155.91000014202.00236793,892
2013/04/1154.351000014385.995781,879
2013/05/1057.91000014558.70658842,949
2013/06/1156.351000014736.16887830,383
2013/07/1157.21000014910.99404852,909
2013/08/12551000015092.81222830,105
2013/09/1157.51000015266.72527877,837
2013/10/1158.451000015437.81166902,340
2013/10/2457.5520841.0457515799.94973909,287
2013/11/1156.31000015977.56962899,537
2013/12/1157.851000016150.43047934,302
2014/01/1057.551000016324.19242939,457
2014/02/1156.951000016499.78504939,663
2014/03/1159.351000016668.27704989,262
2014/04/1161.151000016831.809341,029,265
2014/05/1261.151000016995.341631,039,265
2014/06/1164.151000017151.226281,100,251
2014/07/1168.31000017297.639161,181,429
2014/08/1166.051000017449.039621,152,509
2014/09/1168.41000017595.238451,203,514
2014/10/13641000017751.488451,136,095
2014/10/2463.0527514.807118187.885071,146,746
2014/11/1165.951000018339.515091,209,491
2014/12/1165.251000018492.77181,206,653
2015/01/1265.751000018644.863051,225,900
2015/02/11691000018789.790591,296,496
2015/03/1169.051000018934.613181,307,435
2015/04/1069.651000019078.18821,328,796
2015/05/1170.851000019219.331461,361,690
2015/06/1168.851000019364.574741,333,251
2015/07/0967.11000019513.606041,309,363
2015/08/1164.551000019668.524711,269,603
2015/09/1163.51000019826.005021,258,951
2015/10/1265.551000019978.560321,309,595
2015/10/2664.5539957.1206520597.570711,329,573
2015/11/1162.151000020758.471761,290,139
2015/12/1159.851000020925.556141,252,395
2016/01/1156.551000021102.39081,193,340
2016/02/15591000021271.882321,255,041
2016/03/1163.551000021429.238731,361,828
2016/04/11631000021587.968891,360,042
2016/05/1159.851000021755.053271,302,040
2016/06/1363.751000021911.916021,396,885
2016/07/11671000022061.169751,478,098
2016/07/2869.0518751.9942922332.740991,542,076
2016/08/1169.951000022475.700251,572,175
2016/09/1069.41000022619.792471,569,814
2016/10/1171.451000022759.750481,626,184
2016/11/1170.051000022902.505651,604,321
2016/12/1272.851000023039.774011,678,448
2017/01/1172.41000023177.895561,678,080
2017/02/1072.81000023315.25821,697,351
2017/03/10721000023454.147091,688,699
2017/04/1173.91000023589.465081,743,261
2017/05/1176.51000023720.184041,814,594
2017/06/1277.151000023849.801671,840,012
2017/07/1181.551000023972.425821,954,951
2017/07/3181.3516780.6980824178.703611,966,938
2017/08/1181.251000024301.780531,974,520
2017/09/1182.551000024422.919242,016,112
2017/10/1183.4024422.919242,036,871
2017/11/1084.551000024541.192452,074,958
2017/12/1181.51000024663.891842,010,107
2018/01/1183.41000024783.795912,066,969
2018/01/2985.5554524.3510125421.134912,174,778
2018/02/1279.71000025546.605422,036,064
2018/03/1284.151000025665.440832,159,747
2018/04/1182.851000025786.140892,136,382
2018/05/1181.61000025908.689912,114,149
2018/06/1182.651000026029.682052,151,353
2018/07/1181.71000026152.081072,136,625
2018/07/2384.5518306.4567526368.597412,229,465
2018/08/1085.71000026485.283532,269,789
2018/09/1185.651000026602.037762,278,465
2018/10/1177.41000026731.236732,068,998
2018/11/12781000026859.441852,095,036
2018/12/1175.051000026992.686362,025,801
2019/01/1175.51000027125.136692,047,948
2019/01/2274.0562387.8143827967.6462,071,004
2019/02/1175.151000028100.71322,111,769
2019/03/1176.151000028232.032962,149,869
2019/04/1181.151000028355.261552,301,029
2019/05/1081.51000028477.960942,320,954
2019/06/1179.41000028603.905522,271,150
2019/07/1182.851000028724.605582,379,834
2019/07/198320107.2239128966.861292,404,249
2019/08/1280.61000029090.930772,344,729
2019/09/1183.451000029210.763012,437,638
2019/10/0985.81000029327.313122,516,283

單筆投資成果計算

日期價格投入金額總單位數總現值
2007/10/1171.9144000020027.816411440000
2007/10/2467.750069.5410320767.396041,405,953
2008/10/2432.3441534.7920922051.71243713,152
2009/10/2353.2522051.7124322465.82911,196,305
2010/10/2556.149424.8240223346.842011,309,758
2011/10/2652.1545526.3419124219.830341,263,064
2012/10/245144806.6861425098.392821,280,018
2013/10/2457.5533882.830325687.147471,478,295
2014/10/2463.0539815.0785826318.631671,659,390
2015/10/2664.5552637.2633427134.081141,751,505
2016/07/2869.0523063.9689727468.099521,896,672
2017/07/3181.3519227.6696627704.456862,253,758
2018/01/2985.5560949.8050828416.903442,431,066
2018/07/2384.5519891.8324128652.170532,422,541
2019/1/2274.0565899.9922129542.109652,187,593
2019/07/198320679.4767629791.259982,472,675
2019/10/0985.8029791.259982,556,090

結論

  • 短期股市下跌定期定額投資法報酬較優。
  • 單筆投資在第10年時報酬與定期定額投資相近。
  • 時間拉長至12年，單筆投資報酬勝過定期定額投資，主要是因為單筆投資有提早利用投資複利效果增加報酬。
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