(CNN) -- It's been a busy year for the British royal family. The Prince of Wales and the Duchess of Cornwall alone covered almost 48,000 miles to undertake 804 official engagements between April 2011 and the end of March this year. So who pays the bills?
Prince Charles' office at Clarence House released its annual review Friday, shedding light on how money is spent on the couple, as well as Princes William and Harry and, of course, the newest addition to the family, Catherine, Duchess of Cambridge.
As the queen's eldest son, Charles, Prince of Wales, is mostly funded by the Duchy of Cornwall, a private estate consisting of more than 200 square miles of agricultural, commercial and residential land mostly in southwest England.
In the 2011-12 fiscal year, the prince's private income from the duchy rose by 3% to slightly more than $28.5 million. He received an additional $3.42 million in public funding from Parliament and government departments, a year-on-year increase of 11.8%.
With more private and public income, Prince Charles' household spending increased by 4.1% to $15.3 million, and all 135 full-time staff members received a pay raise of 3%. Nine of those employees work for Princes William and Harry, and for Catherine, Duchess of Cambridge.
So what is the expense of the royal family's newest member?
"It's actually quite minimal," said Prince Charles' communications secretary, Paddy Harverson, "There's been quite a lot of focus on things like clothes but actually, when you look at the numbers, it's mostly absorbed into the existing expenditure."
A royal aide added that it would be "rather impolite" to disclose how much money had been spent on the dresses that hit front pages of newspapers around the world every time Catherine steps out in public. What we do know, though, is that Prince Charles pays for his daughter-in-law's outfits for official engagements out of his private income.
Anti-monarchy groups such as Republic have criticized the royal family for using public money to travel. "Prince Charles gives little back to the country yet has a deeply held sense of entitlement when it comes to accessing public funds," Chief Executive Graham Smith said Friday. "We believe time is long overdue that the government brought royal spending under proper control."
However, Harverson maintains: "Members of the royal family do a huge amount of work. ... We really feel it's fantastic value for money. As it happens, 90% of it is his (Prince Charles') own income, so it's not coming from central government coffers."
Royal aides champion the continued success of the prince's group of 16 charities as the greatest example of the royal family giving back to the public. Between April 2011 and the end of March this year, the Prince of Wales directly or indirectly raised more than $200 million for his charities, which support young people, the environment and enterprise.
After last year's royal wedding and the recent Diamond Jubilee celebrations, polls have showed that the British royal family is as popular as ever. Riding high on that wave is the household of the Prince of Wales, as exemplified by the 76,825 letters received from the public in 2011-12. That is more than double the mail from the previous year.