Here you can calculate the total standard tax for savings in an investment savings account (ISK). The tax on investment savings accounts is deducted each year, based on the account's value and deposits during the year, instead of as in a traditional share deposit, where the capital gains tax is deducted only when the holding is sold.
The government borrowing rate is an interest rate that reflects the average long-term borrowing rate for the Swedish government. This interest rate is used as a basis for various calculations. The National Debt Office has more information about the government loan interest rate.
Examples of government loan interest in certain years (approximate values):
From 1 January 2018, 1% is added to the government loan interest to calculate the standard income, and the lowest possible standard income was set at 1.25%. This was done, of course, because of the then extremely low, and sometimes negative, interest rates.
The Swedish Tax Agency explains how the capital base and tax are calculated here.