It is a mistake.
In 1944 have constructed less than 3424 Yak-3.
Production in 1944:
2718 Yak-1 and Yak-3 (a factory № 292);
706 Lagg-3 and Yak-3 (a factory № 31);
Production in 1945:
1559 Yak-3 with gun SHVAK and 2 machine guns BS (a factory № 292);
359 Yak-3 with three guns B-20 (a...