DAX

Hi Community,

Help me with DAX  For,

For Fourth Column,
Row 1 - Month 1, (125679.78/168) = 748.09

Row 2 - Month 2, (58364.12/184) = 317.20
Row 3 - Quarter, 
I want ((125679.78/168) + (58364.12/184) )/DISTINCTCOUNT(Month)= 1065.29
Also,
I want last two months data alone. Currently Month 1 and Month 2 are Last two Months. When Month 3 data gets updated, Month Column must cotain Month 2 and Month 3 and Quarter ( with respect to Last two Months).

Thanks in Advance,
Sowmiya