(The graph above is from page 839 of his original Kursk book.)
He then cites a well-known Soviet Air Force war veteran..."…the Soviet claims do not appear to have been related to the German casualties. Instead, if one compares Soviet losses to Soviet claims of German losses one does find a fit. The pattern is fairly clear, the Soviets always claimed more casualties than they lost. With the Soviets losing 658 planes, and claiming 928 German kills, we are looking at the Soviets claiming about 40 percent more kills than they lost. This over-claiming is fairly consistent from day to day, and as shown elsewhere [in the book], is not a problem unique to the Soviet air force [it was also the case for the Soviet Army]. "
There is at least one claim from Karelian Front in 1944. VVS 324th fighter division (with 3 regiments?) claimed 39 Finnish Curtiss, 18 Brewster, 6 Morane and 1 Bf-109 shot down during Svir-Petrozavodsk Offensive (10 June - 1 August 1944). Finnish records are showing just 4 Morane and 2 Brewster shot down by Soviet aircraft. 3 Morane and 3 Curtiss were shot down by AA-units.A briefing based upon this data was presented to Col. Fyodor Sverdlov in October 1994, who was a staff officer for the Eleventh Guards Army at Kursk and later a professor at the Frunze Military Academy. After presenting the chart showing Soviet claims to German losses, Sverdlov stated that “the enemy always suffers 30% more losses than you.”
When it comes to Winter War there was indeed clear over claim of 411 shot down/destroyed Finnish aircraft. According most studies Finnish AA and FAF units have shot down confirmed (from Soviet sources) at least 250 aircraft but not even near 411. How about Continuation War 1941-44 both in Karelian Isthmus and Karelian Front? What were the official Soviet claims of Finnish/German losses there in 1941, 1942, 1943, 1944?