Month	Passenger-Miles
1920-01-01	75.8000
1920-02-01	74.7000
1920-03-01	77.0000
1920-04-01	80.7000
1920-05-01	81.8000
1920-06-01	90.2000
1920-07-01	98.8000
1920-08-01	103.000
1920-09-01	92.2000
1920-10-01	80.3000
1920-11-01	77.0000
1920-12-01	75.5000
1921-01-01	71.4000
1921-02-01	67.9000
1921-03-01	66.0000
1921-04-01	63.7000
1921-05-01	65.3000
1921-06-01	71.9000
1921-07-01	77.4000
1921-08-01	77.1000
1921-09-01	73.3000
1921-10-01	64.4000
1921-11-01	60.4000
1921-12-01	62.0000
1922-01-01	59.5000
1922-02-01	58.8000
1922-03-01	57.4000
1922-04-01	62.0000
1922-05-01	62.3000
1922-06-01	72.3000
1922-07-01	76.0000
1922-08-01	77.7000
1922-09-01	75.7000
1922-10-01	67.7000
1922-11-01	63.9000
1922-12-01	68.3000
1923-01-01	63.8000
1923-02-01	62.3000
1923-03-01	61.7000
1923-04-01	64.5000
1923-05-01	64.8000
1923-06-01	76.2000
1923-07-01	78.1000
1923-08-01	80.6000
1923-09-01	77.6000
1923-10-01	66.2000
1923-11-01	63.2000
1923-12-01	68.8000
1924-01-01	63.0000
1924-02-01	61.9000
1924-03-01	60.7000
1924-04-01	61.3000
1924-05-01	61.4000
1924-06-01	72.8000
1924-07-01	72.6000
1924-08-01	77.0000
1924-09-01	70.4000
1924-10-01	60.5000
1924-11-01	59.3000
1924-12-01	62.1000
1925-01-01	61.2000
1925-02-01	60.1000
1925-03-01	56.3000
1925-04-01	57.3000
1925-05-01	60.3000
1925-06-01	72.0000
1925-07-01	74.1000
1925-08-01	78.8000
1925-09-01	73.1000
1925-10-01	62.9000
1925-11-01	60.4000
1925-12-01	63.2000
1926-01-01	62.1000
1926-02-01	61.1000
1926-03-01	56.8000
1926-04-01	58.9000
1926-05-01	60.8000
1926-06-01	71.2000
1926-07-01	73.3000
1926-08-01	74.8000
1926-09-01	71.4000
1926-10-01	61.3000
1926-11-01	58.6000
1926-12-01	62.2000
1927-01-01	60.7000
1927-02-01	59.3000
1927-03-01	55.2000
1927-04-01	58.3000
1927-05-01	60.2000
1927-06-01	67.8000
1927-07-01	71.3000
1927-08-01	70.9000
1927-09-01	68.7000
1927-10-01	59.0000
1927-11-01	56.6000
1927-12-01	59.7000
1928-01-01	58.3000
1928-02-01	56.8000
1928-03-01	53.7000
1928-04-01	57.0000
1928-05-01	55.9000
1928-06-01	67.4000
1928-07-01	68.3000
1928-08-01	69.9000
1928-09-01	67.8000
1928-10-01	57.5000
1928-11-01	54.8000
1928-12-01	59.1000
1929-01-01	57.5000
1929-02-01	59.2000
1929-03-01	56.9000
1929-04-01	56.0000
1929-05-01	56.9000
1929-06-01	67.9000
1929-07-01	67.3000
1929-08-01	70.8000
1929-09-01	65.2000
1929-10-01	55.3000
1929-11-01	53.3000
1929-12-01	58.3000