During the period from 2000 to 2021, 77% (5,894,667 of 7,633,131) of all trace requests were completed. Since 2016, the trace
completion rate has remained above 80%, the system is better and the market is full of newer post 68 firearms. Of the 23% of requests that were not completed, 1,738,464 trace requests in total, 366,281 (4.7%) requests were duplicates, 44,785 (0.58%) were stopped by requestor, 869,440 (11.4%) had invalid or inadequate firearm markings, and 457,958 (6%) were pre-GCA weapons and not required to be marked, as they were made prior to the 1968 Gun Control Act which began requiring specific marking.
During the time period, 2000 to 2021, a total of 401,545,091 requests were submitted to FBI NICS and denials (including 1998 and 1999) were only 2,039,507. So in the majority of the history of our national background check system and the mandate to use it by federal dealers, only 0.5% were
denied the transfer. 1 in 200.