What is percentile. I am learning calculating percentiles. Lets say we have 10 numbers 12,23,45,67,7,99,23,12,45,34. If you want to calculate 90th percentile then is it (90/100)*10=9.
So is number 9 greater then 90% of the numbers.
Wikipedia article on percentile
The 90-th percentile for your data is a value that is greater than 90% of the data. First sort your data into ascending order:
7, 12, 12, 23, 23, 34, 45, 45, 67, 99
which because the data is so sparse would strictly be 99. However Excel would calculate this to be 67+0.1*(99-67)=70.2.
Anything above 67 would be a 90-th percentile, but if it has to be a data value it has to be 99.