Rule to Convert Wage Types from RT to IT.

Hi Guys, good night, I hope you are always fine:

Can somebody help with an example to convert Wagw Types from an RT to an IT?

For example, If I have Wage Types in RT:  1000, 1001, 1002, 1003, 1004

Can somebody explain me the rule in detail?

I will appreciatte this help.

Thanks in advance for your help.