Month	Millions Of Books
1919-01-01	10.5700
1919-02-01	8.41000
1919-03-01	8.38000
1919-04-01	8.44000
1919-05-01	8.26000
1919-06-01	9.82000
1919-07-01	8.51000
1919-08-01	10.7800
1919-09-01	11.1700
1919-10-01	11.6300
1919-11-01	10.6300
1919-12-01	11.6000
1920-01-01	11.2800
1920-02-01	10.2200
1920-03-01	11.1400
1920-04-01	6.28000
1920-05-01	12.7300
1920-06-01	12.2700
1920-07-01	11.9800
1920-08-01	11.9300
1920-09-01	12.4400
1920-10-01	11.8400
1920-11-01	11.0300
1920-12-01	10.2600
1921-01-01	8.88000
1921-02-01	7.99000
1921-03-01	6.92000
1921-04-01	7.44000
1921-05-01	6.70000
1921-06-01	7.10000
1921-07-01	6.11000
1921-08-01	9.38000
1921-09-01	10.1800
1921-10-01	9.88000
1921-11-01	9.36000
1921-12-01	9.25000
1922-01-01	9.04000
1922-02-01	9.01000
1922-03-01	9.78000
1922-04-01	8.73000
1922-05-01	9.49000
1922-06-01	10.7700
1922-07-01	8.61000
1922-08-01	11.8300
1922-09-01	10.1000
1922-10-01	11.4200
1922-11-01	11.1700
1922-12-01	11.0600
1923-01-01	11.4800
1923-02-01	10.6000
1923-03-01	12.5100
1923-04-01	10.9600
1923-05-01	11.3300
1923-06-01	11.3300
1923-07-01	9.70000
1923-08-01	12.2400
1923-09-01	11.6700
1923-10-01	12.6300
1923-11-01	11.9100
1923-12-01	11.5000
1924-01-01	11.2600
1924-02-01	11.6600
1924-03-01	11.4400
1924-04-01	10.5700
1924-05-01	10.3800
1924-06-01	11.7300
1924-07-01	9.88000
1924-08-01	11.0400
1924-09-01	11.7500
1924-10-01	12.5800
1924-11-01	10.8000
1924-12-01	12.0300
1925-01-01	11.1900
1925-02-01	11.3800
1925-03-01	12.8700
1925-04-01	11.5600
1925-05-01	11.2800
1925-06-01	13.0500
1925-07-01	9.53000
1925-08-01	12.0400
1925-09-01	12.9700
1925-10-01	12.6500
1925-11-01	12.1700
1925-12-01	12.2700
1926-01-01	11.1100
1926-02-01	11.5000
1926-03-01	13.0700
1926-04-01	11.9100
1926-05-01	11.5400
1926-06-01	12.4300
1926-07-01	9.58000
1926-08-01	12.6200
1926-09-01	12.1000
1926-10-01	12.8100
1926-11-01	12.3900
1926-12-01	12.5400
1927-01-01	11.1800
1927-02-01	11.2000
1927-03-01	12.5200
1927-04-01	11.1700
1927-05-01	10.7800
1927-06-01	12.7100
1927-07-01	8.87000
1927-08-01	13.4500
1927-09-01	12.3900
1927-10-01	12.9000
1927-11-01	13.0900
1927-12-01	12.9300
1928-01-01	11.9000
1928-02-01	11.7200
1928-03-01	11.9300
1928-04-01	11.8100
1928-05-01	11.6400
1928-06-01	13.1000
1928-07-01	9.99000
1928-08-01	13.7400
1928-09-01	11.9800
1928-10-01	14.6000
1928-11-01	13.0800
1928-12-01	12.4600
1929-01-01	12.1700
1929-02-01	11.9800
1929-03-01	12.4100
1929-04-01	12.1800
1929-05-01	12.1500
1929-06-01	12.4500
1929-07-01	11.4800
1929-08-01	13.6300
1929-09-01	12.2300
1929-10-01	14.1500
1929-11-01	12.7800
1929-12-01	11.8200
1930-01-01	11.9900
1930-02-01	11.5900
1930-03-01	12.1800
1930-04-01	12.2400
1930-05-01	10.9700
1930-06-01	12.5400
1930-07-01	10.5700
1930-08-01	11.9200
1930-09-01	12.3600
1930-10-01	13.4300
1930-11-01	10.7200
1930-12-01	10.8900
1931-01-01	10.4500
1931-02-01	10.6500
1931-03-01	10.6700
1931-04-01	11.0800
1931-05-01	10.5800
1931-06-01	10.3800
1931-07-01	10.0000
1931-08-01	10.5000
1931-09-01	11.2400
1931-10-01	10.6600
1931-11-01	9.55000
1931-12-01	9.31000
1932-01-01	9.20000
1932-02-01	8.46000
1932-03-01	9.78000
1932-04-01	8.73000
1932-05-01	9.26000
1932-06-01	9.00000
1932-07-01	8.27000
1932-08-01	9.13000
1932-09-01	8.70000
1932-10-01	9.08000
1932-11-01	8.87000
1932-12-01	9.07000
1933-01-01	7.92000
1933-02-01	7.65000
1933-03-01	8.05000
1933-04-01	8.57000
1933-05-01	9.57000
1933-06-01	11.1600
1933-07-01	11.1000
1933-08-01	11.9500
1933-09-01	10.4800
1933-10-01	11.6300
1933-11-01	10.5400
1933-12-01	9.67000
1934-01-01	11.2200
1934-02-01	9.93000
1934-03-01	10.9500
1934-04-01	10.6600
1934-05-01	11.4000
1934-06-01	11.4700
1934-07-01	11.3600
1934-08-01	13.0100
1934-09-01	10.7900
1934-10-01	12.9200
1934-11-01	11.4000
1934-12-01	11.5900
1935-01-01	11.8200
1935-02-01	10.7400
1935-03-01	11.3600
1935-04-01	12.1000
1935-05-01	11.9100
1935-06-01	11.6700
1935-07-01	12.6800
1935-08-01	12.9300
1935-09-01	12.9100
1935-10-01	14.8000
1935-11-01	13.1200
1935-12-01	13.1300