Bp is the base point, which is the abbreviation of English basis point. This code appears in various transactions. For example, if the exchange rate rises by one basis point, such as 1 USD =6.8534 RMB, it becomes 6.8545, which is called the rise 10 point (basic words are generally omitted). In the exchange rate, one ten thousandth is a point (a few units, such as the Japanese yen, have a smaller value of 1%).
The loan interest rate is 3%, plus 100bp is 4%.