Table:
text: 1990s in video gaming
Best-selling video games of the decade
Best-selling video games of the 1990s (sale numbers as of 25 February 2012)[ 
 citation needed 
 ]
Rank_ Title Release_Date Franchise Developers Platform Units_sold_in_Millions
7 Gran Turismo 23 December 1997 Gran Turismo Polyphony Digital PlayStation 11.15
8 Super Mario All-Stars 14 July 1993 Super Mario Bros. Nintendo SNES 10.55
9 Mario Kart 64 14 December 1996 Mario Kart Nintendo Nintendo 64 9.87

Question: What day did the 1990s video game platform sell 9.87 million units?