Conditional Formatting - Formulas Issue

[Tony_Manero]

I've created a spreadsheet which monitors the daily weights of animals and added conditional formatting so if the cell drops below 20% of their body weight it turns red

I have the following formula where it calculates 20% of body weight of an animal

=D4%80

that was easy but I'm having problems creating another formula with the following stipulation

for animals weighing 25g or more, rapid weight loss of 15% over two to three days

So I need to calculate if the weight is 15% less than 3 cells earlier, ideally flagging as red or yellow, is this possible?

 

[mart37]

something like this: =IF(D4>25,MIN(range with 2 or 3 days earlier)<D4*85%,FALSE)

when red?when yellow?