Serial number range: 2411001-3779779 (1970-1997, approx. 54,010 produced). Production by year: 1970: #2411001-2442000 (2,020 units); 1971: #2478701-2480700 (2,000 units); 1972: #2509601-2544500 (5,250 units); 1974: #2669451-2726920 (4,000 units); 1976: #2783651-2805400 (4,000 units); ... ; 1992: #3583831-3583860 (30 units); 1993: #3624801-3625300 (500 units); 1994: #3664831-3665830 (1,000 units); 1995: #3700302-3701301 (1,000 units); 1997: #3778780-3779779 (1,000 units)