Construct statutory paternity pay from the FRS (sppadj) #575

What happens

policyengine_uk_data/datasets/frs.py sets statutory_sick_pay = person.sspadj * WEEKS_IN_YEAR and statutory_maternity_pay = person.smpadj * WEEKS_IN_YEAR, and nothing sets statutory_paternity_pay. The certified enhanced FRS (1.58.0) has no statutory_paternity_pay column. policyengine-uk has the variable and now taxes it (PolicyEngine/policyengine-uk#2368) and counts it in UC, HB and CTR (#2365, #2368).

What the FRS has

The 2023-24 FRS adult table has columns sppadj, sapadj and shppadj, named like sspadj and smpadj. Positive values: 3 adults for sppadj, 1 for sapadj and 1 for shppadj, against 79 for sspadj and 94 for smpadj (of 28,590 adults).

To decide

• Confirm from the FRS documentation what sppadj records (weekly amount at interview?).
• Whether annualising by 52 weeks is right for a payment that lasts at most two weeks (SPP) — the same question applies to SSP (up to 28 weeks) and SMP (39 weeks).
• Map sppadj to statutory_paternity_pay (and consider adoption and shared parental pay, which policyengine-uk has no variables for yet).

Data releases go out as one batch on Max's go; this is a code change for the next batch.