what yields do tips have 
the yields on tips are often negative this is because after taking into account the effects of inflation the real yield is negative for instance if standard two year treasuries yield 1 but inflation is 2 then the real yield is 1 tips are meant to keep up with inflation not beat inflation therefore you can have a nominal yield on tips that is positive but a real yield that is effectively zero note that while the yield on tips may be negative their principal value will increase with inflation which can generate capital gains 