tableau work

I want to know which stocks volume is more than 2,3,4(by parameter, valid:2,3,4) times than the average 50 day volume. I expect 3 params in this case: (1) volume how much more than the avg volume (2) avg volume of last 50, or 20 days (3) analysis to be done on the latest day or say 5 days back the latest date.(so this param can be: exclude from latest: 0,20) avg_volume for window calc for 50 days can be given by window_avg(trad_volume, -49, 0) The expected output has to be in cross tab, stock name, trade_volume, 50/20 day mov avg, how many times more is trade volume. I feel i am quite ok in tableau, I just dont have time to implement this. I expect the output in cross tab This is an ongoing work, so this workbook already many calculated fields, parameters etc....i can spend upto 3000 INR for this work.