Compare Ratios with difference underlying population sizes

#1
Suppose my product is deployed to multiple regions and I want to compare if Daily Revenue(DR)/Daily Active Users(DAU) for US and Japan are the same.

Now I collect 14 data points(14 days, each day produce one data point) for US and Japan respectively.

However the DAU for US is ~1 Million and the DAU for Japan is ~100. Can I still use t-test formula to compare 2 ratios without considering underlying DAU/DR huge difference?
 

hlsmith

Not a robit
#2
Can you better show us what your data look like? Are you looking to plot to time series and compare slopes or look at daily differences? More information is needed.