Figures just released by the Conseil des Ventes, France's auction watchdog, list Chinese auction houses China Guardian and Poly, as well as US saleroom Heritage, as having higher totals. However, Bonhams say that the Conseil has got its figures wrong.
In straightforward terms, the Conseil lists Heritage as having the fifth highest total with €662m in sales, with Bonhams next at €661m, but Bonhams say their totals are €677m, which would put them clearly ahead.
Meanwhile the China Guardian total is listed as €796m and that of Poly as €795m. However, Bonhams say that settlement rates - how much is actually paid for - should be taken into account as they are so low in China.
Poly admit to a settlement rate of 55%, which would put their total at around €437m. Although China Guardian are not thought to have revealed their settlement rate, the latest TEFAF report puts the average rate in mainland China at 56% - almost exactly that of Poly - which would mean China Guardian's rate would have to be close to that. If so, total actual sales would be around €446m.
Bonhams report a settlement rate for their global sales at more than 99%.
Varying exchange rates can skew results further. For instance, the Conseil lists Sotheby's as having taken €4.05bn in sales for 2013, while exchange rates used in Sotheby's own release last month would put that figure closer to €4.76bn.
A gap of close to three quarters of a billion euros in reported totals simply based on using different exchange rates is less than helpful when trying to gauge comparative performances of rivals on the global auction stage.
As the TEFAF report shows, with global totals almost back at the 2007 record levels, there is a great deal to play for, so sensitivity over results is likely to run deep whichever auction house you work for.