How to calculate if contract date is active or no expiration date

[lynettejackson]

I'm having trouble adding a new column with a date formula that determines whether or not a contract is active. I'm creating a process utilizing the [contract line start date] and [contract line end date].

I have attached the file 

TechidentNo and Technical Identification are my join fields.  The expiration is 03/31/2022.

I would deeply appreciate any assistance I can get.

[Qiu · Accepted solution]

@lynettejackson 
I am not quite able to understand the logic here. Just wild guess. 😁

[lynettejackson]

Thank you so much.  The workflow worked.  I have save formula for future reference.  Again, thanks  a lot.