It has four tabs. Members is the register — add each person once and their totals roll up automatically. Contributions is a simple log with a member dropdown. Loans records each loan's principal, monthly interest and term; interest, total repayable and the outstanding balance compute themselves, and the status shows OPEN, PARTIAL or CLEARED as members repay. The Dashboard shows total collected, loans issued, outstanding, interest earned and the fund's cash on hand.
Interest is simple flat interest (principal × monthly rate × term) — the model most chamas use — and you can change the rate or term on any loan row. Everything is a formula; only the yellow cells accept typing, so members can read the book without breaking it.
Share the Google Sheets version with your officials so everyone sees the same numbers, or keep it in Excel for month-end statements.