Analysis Of Short Term Treasury ETF to Park CASH

List of good ETF's to park money for short term (~1 month) while waiting for opportunities.

Criteria: Some yield (above the low interest rates available from money markets), low volatility, high liquid, low bid/ask spread.

Barclays iShares US Treasury Bond ETFs
iShares Lehman Short Treasury Bond Fund (SHV)
iShares Lehman 1-3 Year Treasury Bond Fund (SHY)
iShares Lehman 3-7 Year Treasury Bond Fund (IEI)
iShares Lehman 7-10 Year Treasury Bond Fund (IEF)
iShares Lehman 10-20 Year Treasury Bond Fund (TLH)
iShares Lehman 20+ Year Treasury Bond Fund (TLT)

State Street SPDR US Treasury Bond ETFs
SPDR Lehman 1-3 Month T-Bill ETF (BIL)
SPDR Lehman Intermediate Term Treasury ETF (ITE)
SPDR Lehman Long Term Treasury ETF (TLO)

Vanguard Government Bond Index ETFs
Vanguard Short-Term Government Bond Index Fund (VGSH)
Vanguard Intermediate-Term Government Bond Index Fund (VGIT)
Vanguard Long-Term Government Bond Index Fund (VGLT)

Inflation Protected Bond [TIPS] ETFs
iShares Lehman TIPS Bond Fund (TIP)
SPDR Barclays TIPS ETF (IPE)

Analysis TBD