Why were the brokage books compiled?

showing 'Cristmas Daye' in left hand margin

'St Thomas Day' in left hand margin

It was the responsibility of the Bargate Broker to collect the three tolls of brokage, local custom and pontage on carts as they passed in and out through Southampton’s north gate, or Bargate. While keeping a record of the tolls paid on the commodities being carried, the broker, or his scribe, wrote down the quantity of goods carried; the name of the carters who conveyed the goods, the people who owned them, and their destination. These records, or detailed accounts, now known as the brokage books, were compiled so that they could be tendered at the end of each year to the town corporation for audit.