my $day   = ( $short_int & 0b0000000_0000_11111 )      ;
my $month = ( $short_int & 0b0000000_1111_00000 ) >> 5 ;
my $year  = ( $short_int & 0b1111111_0000_00000 ) >> 9 ;

my $date  = sprintf "%04d-%02d-%02d", 1980 + $year, $month, $day;