dart production numbers.

YEAR MODEL NUMBER SOLD NOTES
1960 All Darts combined 306,603 Full-size Darts
1961 Dart Seneca 66,100 Figures are rounded to the nearest 100.
Dart Pioneer 38,600
Dart Phoenix 37,300
1962 Dart 48,200 Figures are rounded to the nearest 100.
Dart 330 25,500
Dart 440 37,800
Dart wagon 24,400
1963 Dart 170 51,300 This is the first year for the compact Dodge Dart. Figures are rounded to the nearest 100.
Dart 270 55,300
Dart wagon (170/270) 13,000
1964 Dart 170 Six 68,000 Figures are rounded to the nearest 100.
Dart 170 V8 2,200
Dart 270 Six 53,700
Dart 270 V8 6,700
Dart Six wagon (170/270) 12,900
Dart V8 wagon (170/270) 1,100
Dart GT Six 38,200
Dart GT V8 12,500
1965 Dart 170 Six 70,900 Figures are rounded to the nearest 100.
Dart 170 V8 2,900
Dart 270 Six 52,900
Dart 270 V8 9,900
Dart Six wagon (170/270) 23,400
Dart V8 wagon (170/270) 6,000
Dart GT Six 22,700
Dart GT V8 18,000
1966 Dart 170 Six 28,400 Figures are rounded to the nearest 100.
Dart 170 V8 1,400
Dart 270 Six 28,500
Dart 270 V8 6,600
Dart Six wagon (170/270) 20,900
Dart V8 wagon (170/270) 8,400
Dart GT Six 8,700
Dart GT V8 10,000
1967 Dart Six 50,900 Figures are rounded to the nearest 100.
Dart V8 2,200
Dart 270 Six 49,700
Dart 270 V8 13,500
Dart GT Six 16,600
Dart GT V8 21,600
1968 Dart Six 56,900 Figures are rounded to the nearest 100.
Dart V8 3,400
Dart 270 Six 55,200
Dart 270 V8 21,300
Dart GT Six 10,900
Dart GT/GTS V8 24,100
1969 Dart Six 61,800 Figures are rounded to the nearest 100.
Dart V8 24,600
Dart Swinger 20,000
Dart Custom Six 41,600
Dart Custom V8 22,100
Dart GT Six 5,600
Dart GT V8 15,300
Dart GTS V8 6,700
1970 Dart 4-door sedan 35,449 "Exactly 191,986 Dodge Dart/Dart Custom/Dart Swinger
and Dart Swinger 340 passenger cars were built during model
year 1970. In rounded-off totals, this included only 3,900
units built in the United States. The additional cars, some
188,100 in all, were manufactured, in Canada, for the U.S.
market. Six-cylinder engines were installed in 69.7 percent of these cars and the rest were V-8s."
Dart Swinger 119,883
Dart Swinger 340 13,785
Dart Custom 4-door 23,779
Dart Custom 2-door hardtop 17,208
1971 Demon 69,861
Demon 340 10,098
Dart 4-door sedan 32,711
Dart Swinger Special 13,485
Dart Swinger 102,480
Dart Custom 21,785
1972 Demon 39,880 "The production total for [Demon 340] is based on
rounded-off model-year records that include only
U.S. built cars. The production total for [the other
1972 Demons and Darts] appears to be an exact
model year record covering all cars built in the U.S.
and Canada, for the U.S. market."
Demon 340 8,700
Dart 4-door sedan 26,019
Dart Swinger Special 19,210
Dart Swinger 119,618
Dart Custom 49,941
1973 Dart Sport 68,113
Dart Sport 340 11,315
Dart 4-door sedan 21,539
Dart 2-door hardtop 17,480
Dart Swinger 107,619
Dart Custom 62,626
1974 Dart Sport Six 40,293 Figures are U.S. built cars only; Canadian cars built for the U.S. market are not included.
Dart Sport V8 23,225
Dart Sport 360 (V8) 3,951
Dart 4-door sedan unspecified
Dart Swinger Special Six 14,211
Dart Swinger Special V8 1,944
Dart Swinger Six 56,126
Dart Swinger V8 33,116
Dart Custom Six 50,047
Dart Custom V8 28,169
Dart Special Edition Six 3,111
Dart Special Edition V8 9,274
1975 Dart Sport Six 28,391 Figures are U.S. built cars only; Canadian cars built for the U.S. market are not included.
Dart Sport V8 8,801
Dart 4-door sedan Six 17,600
Dart 4-door sedan V8 1,749
Dart Swinger Special Six 6,705
Dart Swinger Special V8 323
Dart Swinger/Custom Six 75,105
Dart Swinger/Custom V8 18,452
Dart Special Edition Six 7,393
Dart Special Edition V8 6,578
1976 Dart Sport 13,642
Dart 4-door sedan 27,849
Dart Swinger Special 3,036
Dart Swinger 8,937

Additional information on the GTS Darts may be found at Muscle Cars Production Numbers Database -- thanks to Brian Lynch for the tip!

I did some quick work with a calculator on the sales figures with the following results:

Total U.S. Dart sales from 1963-1976 (compact Darts): 3,738,112
Total U.S. Dart sales from 1960-1962 (full-size Darts): 584,503
Total U.S. Dart sales from 1960-1976 (all U.S. Darts): 4,322,615