My VLOOKUP does not appear to work correctly. Given the following:

AI AJ VLOOKUP("Chores",AI2:AI6,0) = "Chores"
as expected
2 "Chores 8 but VLOOKUP("Chores",AI2:AI6,1) = ERR
3 "Fun 4
4 "Sleep 8
5 "Meals 2.5
6 "Service 3.0

Any insight or advice would be appreciated.
(By the way, this VLOOKUP only takes 3 parameters.)