Used Turbo Tax 8 yrs. I'm retired, husband is sole proprietor part time. Turbo shows 4 exemptions in past. No W2s, no taxes held now. When do I change exemptions to 2?

No dependents now, kids grown.  Husband pays Self Employment tax and estimated taxes.  We report all 1099-MISC.  Both of us on Soc Sec and I have pensions.  No taxes held.