Percentile formula not working properly

[Jokoni]

Im doing up massive amount of data which will be continuously updated in near future, therefore im trying to create formulas that can aid me with my data keying and update accordingly. Now im stuck with the percentile formula, which im trying to get MIC50 and MIC90 from my raw data. However I kept getting 0 and not projecting the actual value.

The 0 values which u see below in the example is from a IF formula which i created to change eg >=64 into 64 so that the percentile formula can work. Those cells that are empty will result in 0 in the cells. As I mentioned earlier that I wanted to create a formula that updates itself when i key in more data in the future, i highlighted the whole column down to the last using Ctrl+Shift before entering. But it results in 0 value. My formula is =PERCENTILE.EXC('Cryo & MIC (2)'!R[-5]C[15]:R[813]C[15],0.9). I have filtered my data therefore there is a mixture of non-formula cells and formula cells, both with and without data (0 and empty cells).

Please help!

Legend: Fo=formula
eg
[TABLE="width: 64"]
<TBODY>[TR]
[TD]0.25(fo)
[/TD]
[/TR]
[TR]
[TD]8(fo)</SPAN>
[/TD]
[/TR]
[TR]
[TD]8(fo)</SPAN>
[/TD]
[/TR]
[TR]
[TD]8(fo)</SPAN>
[/TD]
[/TR]
[TR]
[TD]16(fo)</SPAN>
[/TD]
[/TR]
[TR]
[TD]8(fo)</SPAN>
[/TD]
[/TR]
[TR]
[TD]8(fo)</SPAN>
[/TD]
[/TR]
[TR]
[TD]</SPAN>64(fo)
[/TD]
[/TR]
[TR]
[TD]0.25(fo)</SPAN>
[/TD]
[/TR]
[TR]
[TD]0(fo)</SPAN>
[/TD]
[/TR]
[TR]
[TD]32(fo)</SPAN>
[/TD]
[/TR]
[TR]
[TD]0.25(fo)</SPAN>
[/TD]
[/TR]
[TR]
[TD]0.25(fo)</SPAN>
[/TD]
[/TR]
[TR]
[TD]0.25(fo)
0(fo)
0(fo)
0(fo)
0(fo)
0(fo)
empty
empty
empty
[/TD]
[/TR]
</TBODY>[/TABLE]