Gerry Holtham was commissioned by the Welsh government to look at the pros and cons of the way that government gets its budget.
He found, among other things, that Wales would be treated more generously if Wales were funded on the basis of need rather than the population-based Barnett formula.
Politicians have used his findings ever since to make the case for a change to the formula on the basis of the shortfall suffered by the Welsh government.
I've been talking to Gerry Holtham as part of a discussion on a report he wrote for the Institute of Welsh Affairs. So how big is that shortfall?
He told me: "At the time we did the research it was Â£300 m to Â£400 m a year less than it would get if it were an English region getting needs-based grants. We don't know what that is now.
"Given the squeeze on public finances it's probably a smaller number, the shortfall is probably less than it was then. Even then, it was only a couple of per cent of the Welsh budget so we're probably down to one per cent of the Welsh budget."
In comments that may yet be worth recalling the next time you hear a politician use his figures, he added: "It's not going to change the world. Welsh government has to find a way forward apart from just complaining about the grant."

Paul Simmons-Turner, of East Ham, London, was killed in what police believe was a targeted attack on Tuesday at the Marriott Hotel in Waltham Abbey, Essex.
An inquest into his death has opened and adjourned.
Essex Police said the dead man had been wanted for questioning over an assault in Loughton in May.
Coroner Caroline Beasley-Murray, sitting at the court in Chelmsford, said she was waiting for a full post-mortem examination and toxicology report and the next hearing would be on 9 January.
Mr Simmons-Turner, a father of three, was shot in the hotel car park at about 09:45 GMT and then chased on foot.
He flagged down a passing motorist who drove him to nearby pub The Volunteer, but paramedics could not save him.
Police said a suspect was seen getting into a dark-coloured car being driven by an accomplice following the shooting.
Read more on this and other news from across Essex

The letter, written at the end of the 1916 Easter Rising, had a guide price of 1-1.5m euros.
It was the last official letter Pearse wrote, three days before his execution by firing squad on 3 May 1916.
Pearse wrote it from his prison cell to rebels still fighting in the Four Courts in Dublin.
It reads: "In order to prevent further slaughter of the civil population and in the hope of saving the lives of our followers, the members of the Provisional Government present at headquarters have decided on an unconditional surrender, and commandants or officers commanding districts will order their commands to lay down arms. PH Pearse, Dublin, 30th April 1916."
The details of the item on the James Adam's auction house website quotes historian Diarmaid Ferriter: "Behind the single sentence of the communication lie many layers.
"It was the last official letter Pearse wrote, three days before his execution by firing squad on the morning of May 3rd 1916 and is therefore a vital part of the archive of the newly declared republic in 1916.
"It marked the end of the 1916 rebellion and underlined the role of both the rebel leaders and the British forces in bringing the fighting to a conclusion.
"It is also a reminder of some of the difficulties associated with the rebels military strategy in 1916, especially communications, but also the success in securing certain positions in the midst of urban warfare."
Although the identity of the seller has not been revealed, he has been described by the auctioneers as non-Irish and living outside the country.
In a statement, Stuart Cole, a director at Adam's, said: "On this occasion, the reserve was not met.
"The owner, based overseas, has requested that Adam's apply for an export licence tomorrow (Thursday) to formally notify the [Irish] government that the document will be leaving Ireland and for the process to be expedited.
"The owner was saddened that the government refused to bid for the document but now feels relieved of his obligations to keep the document in Ireland."
He is Wales's most quoted economist, his name often called in aid by those who think the country is under-funded from Westminster.
[NEXT_CONCEPT]
A 38-year-old man killed outside a hotel was shot in the chest with a handgun, an inquest has heard.
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A letter of surrender written by Irish rebel Patrick Pearse has been withdrawn from auction in Dublin after bidding stalled at 770,000 euros (Â£650,000).