U.S. Treasury Interest rate swap spreads

Late last week I was trading a spread of 3:2 cons in the 5 year vs 10 year (ZF vs ZN) I only traded it a few times Thursday and Friday, but it seems something thats fairly profitable. Does anyone have any more info on interest rate swaps??? I also did a 1:1 ratio and couldn't tell much difference. ex, long 1 ZF and short 1 ZN at the same time, and wait for the spread to widen into a profit before exiting both at the same time)

I did something like this a while back on the NQ vs ES but it was not consistent enough some days it would be 2:1 then 3:1, 5:3, 1:1 ect ect. I think vix in Treasury's are almost the same from market to market.

here's a link for ratio's

http://www.cmegroup.com/trading/interest-rates/files/ICS_Ratios__December_2009_Contracts.pdf