dr ron, the easiest way probably is to use "lookup" functions, so in an unused area of the worksheet, for example at AA1 enter 0, AA2 enter .05 & so on, in cell AB1 enter 100, AB2 enter 90 & so on. then create a lookup function in cell I1 which will look something like this -

=LOOKUP(H1,AA$1:AA$11,AB$1:AB$11) & copy it down to cell I2 & so on.

basically it looks at the value in cell H1, finds that value in the cell range AA1 to AA11 & reports the value of the neighbouring cell in the range AB1 to AB11.

note that the ranges AA1 to AA11 & AB1 to AB11 will vary depending on how large your kg & points list is.

if the above makes no sense you are welcome to email me your spreadsheet & i will setup for you.

mango_madness@bigpond.com