The COVID-19 pandemic has collectively caused a $4.7 billion dent to public sector finances over three years, but South Australian Treasurer Rob Lucas says the state is rebounding faster than Victoria, Queensland and NSW and will be back to reporting a yearly surplus by 2022-23.

Mr Lucas, who described himself on Tuesday as “normally a pretty miserable person, pessimistic at best”, said he was more optimistic about the state’s prospects than at any other stage of a 40-year parliamentary career.