I can not find 2 datas : Average return on USA stocks (history) & Return on US gvnt bonds. Can you ?

Hello ,
I am trying to calculate the risk premium , required rate of return , etc , for a stock .
My problem is that I am missing a g (growth ) wich I could find thanks to the average yearly return on US stocks and the difference with the return on gouvernment Bonds (for the last 30 years ) . My problem is that I can not find those datas anywhere . Then I can not make any analysis on the company I have choosen wich is trade on Nasdaq .

Please can you help me ?
Maybe you have an alternative solution ?
Thank you very much .
PS : This is very important for me ...I have to make a report , give recommendations .