Month Hours 1984-01-01 158.4 1984-02-01 152.7 1984-03-01 157.7 1984-04-01 135.3 1984-05-01 155.4 1984-06-01 144.6 1984-07-01 143.8 1984-08-01 142.8 1984-09-01 143.3 1984-10-01 160.8 1984-11-01 151.3 1984-12-01 120.9 1985-01-01 154.2 1985-02-01 142.5 1985-03-01 152.2 1985-04-01 139.1 1985-05-01 152.5 1985-06-01 140.2 1985-07-01 147.1 1985-08-01 136.1 1985-09-01 148.5 1985-10-01 160.9 1985-11-01 146.9 1985-12-01 123.7 1986-01-01 152.9 1986-02-01 141.1 1986-03-01 141.0 1986-04-01 150.7 1986-05-01 145.3 1986-06-01 144.6 1986-07-01 148.0 1986-08-01 132.1 1986-09-01 150.7 1986-10-01 159.9 1986-11-01 140.8 1986-12-01 128.5 1987-01-01 148.7 1987-02-01 145.4 1987-03-01 160.5 1987-04-01 146.8 1987-05-01 144.0 1987-06-01 151.4 1987-07-01 146.4 1987-08-01 132.6 1987-09-01 154.9 1987-10-01 155.9 1987-11-01 153.5 1987-12-01 135.8 1988-01-01 145.7 1988-02-01 151.8 1988-03-01 161.5 1988-04-01 141.5 1988-05-01 153.6 1988-06-01 151.5 1988-07-01 137.2 1988-08-01 147.2 1988-09-01 152.1 1988-10-01 149.7 1988-11-01 152.5 1988-12-01 131.3 1989-01-01 153.0 1989-02-01 143.9 1989-03-01 149.3 1989-04-01 137.8 1989-05-01 152.7 1989-06-01 149.6 1989-07-01 137.3 1989-08-01 147.6 1989-09-01 145.8 1989-10-01 152.2 1989-11-01 154.3 1989-12-01 122.1