Duration of stay for multi entry visa

Hello,

What exactly is the meaning of the "duration of stay" field on a multi entry schengen visa. Does it limit the total number of days you can stay in the schengen zone for the validity of the visa across all your visits to the schengen zone? Or is this the max number of days for each individual visit (assuming one does not break the 90/180 rule). To be clear, let's day someone got a multi entry schengen visa from Germany valid from 1/1/2024 to 31/12/2026. They stay 90 days in Germany, starting 1/1/2024. Then they do not visit the schengen zone until 1/1/2025 when they want to do another trip to Germany for 90 days. Can this still be done on the original visa or does the person need to apply for a new one, as they have already stayed 90 days in schengen zone on that visa?

How Long Can You Stay in Europe With a Schengen Visa?

Double and multiple-entry visas follow the 90/180 rule, where the combined number of days you spend in the Schengen Area in all entries cannot exceed 90 days within a 180-day period.