Formula Field not working without Start date

[Richard_Sather]

Hi @Rachel_Hazen , have a look at point 1 here which may help:

12 Formulas to get you started with the new Advanced Editor

Hi everyone! I hope you are all excited about the recent roll out of the Advanced Editor for Formula fields as I recently announced here. That post includes a video where I had the chance to showcase various use cases, so I thought I’d create this post to share more details on how I built them, which will hopefully inspire you while you try out the Advanced Editor for Formula fields (rolling out on Business and Enterprise tiers). 1. Task Duration: Prerequisites: Start & Due …

You can also try replacing your 0 with 1.