[nickm001]

I have not tried this ..but it should work in theory..
one way is to add @YM as data2 to your chart, overlay it over the existing data1( @YM.D). Use the same interval as in data1. Modify your pivot point code to use data2 for calculation, for example..
var: pivot(0, data2);
( pivot = ( HighD of data2 + LowD of data2 + CloseD of data2)/3 ;