Well this I took it from that table some days ago to see how much SP I will get on each level.
For 0 Gap
0,0396*XP^0,6465
For 1 Gap
0,0484*XP^0,6465
For 2 Gap
0,0597*XP^0,6465
For 3 Gap
0,0735*XP^0,6465
For 4 Gap
0,0924*XP^0,6465
Note: the formulas are set for levels 65 and more and are quite accurate, but they fail on the 63 level experience jump so cant be used before.
Put the XP needed to level up just grinding on the formula and it will give you the SP you will get on that level.
To see the XP needed to level up you can see it on
http://sro.mmosite.com/guides/sp.shtml
I think that somebody else do it previously, but I didnt want to search all the forums so I get my own formulas

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Ive done this to found this result
SP that you will get from going 71 to 80 just grinding:
0 Gap: 55214
1 Gap: 67484
2 Gap: 83239
3 Gap: 102481
4 Gap: 128833
May be somebody else could check that is correct. I just extrapolated the tendance of XP and SP that we get from going from 66 to 70 to the higher levels.
Im just 51 so I couldnt check the values, so if some high level can confirm this will make me a favor because I'm planing my last farming

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