Keep in mind the "one letter five numbers" code was used for all Zeiss-Ikon cameras (not only for Contax) so these codes do not indicate total Contax production.
Serial Numbers for Contax I
T 1931/32
U 1932/33
V 1933/34
X 1934
Y 1934/35
Z 1935/36
A 1936
An extra letter, before or after the serial block letter, indicates the camera was sent back to the camera for repair. Contax I's WITHOUT a 2nd repair letter code are very hard to find!
Vintage Excellent Fresh CLA by the former chief Leica Technician at Essex Camera.