硬碟容量短少? @ 心靈之緣

1.簡單列出一張比對表，讓懶得算、不會算的人，可以直接對照。
2.(公式)實際可用容量 = 硬碟標示容量 x 1000 x 1000 x 1000 / 1024 / 1024 / 1024
3.我只是用 EXCEL 算好再複製貼上，小數點多用了幾位別介意 XD。
4.有錯請指正，我算數不太好。
5.我真的不是黑心硬碟商 0rz 絕對沒有偷大家的容量
6.因為計算法的關係，不論是多大的硬碟，差異比率都會一樣，約為6.86%

硬碟標示      實際可用                差異容量(GB)            差異比率(%)
容量(GB)      容量(GB)
2             1.8626451492309500      0.1373548507690430      6.86774253845215%
4             3.7252902984619100      0.2747097015380860      6.86774253845215%
8             7.4505805969238200      0.5494194030761710      6.86774253845215%
13            12.1071934700012000     0.8928065299987790      6.86774253845215%

16            14.9011611938476000     1.0988388061523400      6.86774253845215%
20            18.6264514923095000     1.3735485076904200      6.86774253845215%
30            27.9396772384643000     2.0603227615356400      6.86774253845215%
40            37.2529029846191000     2.7470970153808500      6.86774253845215%
80            74.5058059692382000     5.4941940307617100      6.86774253845215%
120           111.7587089538570000    8.2412910461425700      6.86774253845215%
160           149.0116119384760000    10.9883880615234000     6.86774253845215%
200           186.2645149230950000    13.7354850769042000     6.86774253845215%
250           232.8306436538690000    17.1693563461303000     6.86774253845215%
300           279.3967723846430000    20.6032276153564000     6.86774253845215%
320           298.0232238769530000    21.9767761230468000     6.86774253845215%
400           372.5290298461910000    27.4709701538085000     6.86774253845215%
500           465.6612873077390000    34.3387126922607000     6.86774253845215%
640           596.0464477539060000    43.9535522460937000     6.86774253845215%
750           698.4919309616080000    51.5080690383911000     6.86774253845215%
960           894.0696716308590000    65.9303283691406000     6.86774253845215%
1000          931.3225746154780000    68.6774253845214000     6.86774253845215%
1280          1192.092895507810000    87.9071044921875000     6.86774253845215%
1500          1396.983861923210000    103.016138076782000     6.86774253845215%