Fidelity 裏買短期T Bill autoroll 也可以,另外考慮稅率
SPAXX 和FZDXX 一個很大的不同是他們的成分,FDLXX能省的州稅要多很多
https://www.fidelity.com/bin-public/060_www_fidelity_com/documents/taxes/GSE-Supplemental-Letter.pdf
FDLXX Treasury Only Money Market Fund 93.63% income exempt from state tax
SPAXX Fidelity Government Money Market Fund ; 30.59% income exempt from state tax