Serial number range: 2402001-3864666 (1970-1999, approx. 35,854 produced). Production by year: 1970: #2402001-2466500 (4,000 units); 1972: #2545701-2545950 (250 units); 1973: #2613001-2620100 (4,100 units); 1974: #2693001-2731920 (2,500 units); 1976: #2783151-2791650 (700 units); ... ; 1988: #3475151-3478150 (3,000 units); 1992: #3583863-3583864 (2 units); 1993: #3617880-3617881 (2 units); 1998: #3843500-3843999 (500 units); 1999: #3864167-3864666 (500 units)