Measuring the number of jobs created per month is limited for longer time periods as the population grows. To address this, we can measure annual job growth percentages, comparing the beginning and ending number of jobs during their time in office to determine an annual growth rate. Jobs grew by 2.0% annually under Reagan, versus 3.1% under Carter, 0.6% under H.W. Bush, and 2.4% under Clinton. The unemployment rate averaged 7.5% under Reagan, compared to an average 6.6% during the preceding eight years. Declining steadily after December 1982, the rate was 5.4% the month Reagan left office. The average real hourly wage for production and nonsupervisory workers continued the decline that had begun in 1973, albeit at a slower rate, and remained below the pre-Reagan level in every Reagan year. The labor force participation rate increased by 2.6 percentage points during Reagan's eight years, compared to 3.9 percentage points during the preceding eight years. Some commentators have asserted that over one million jobs were created in a single month — September 1983. Although official data support that figure, it was caused by nearly 700,000 AT&T workers going on strike and being counted as job losses in August 1983, with a quick resolution of the strike leading workers to return in September, then being counted as job gains. Following the 1981 recession, the unemployment rate had averaged slightly higher (6.75% vs. 6.35%), productivity growth lower (1.38% vs. 1.92%), and private investment as a percentage of GDP slightly less (16.08% vs. 16.86%). In the 1980s, industrial productivity growth in the United States matched that of its trading partners after trailing them in the 1970s. By 1990, manufacturing's share of GNP exceeded the post-World War II low hit in 1982 and matched "the level of output achieved in the 1960s when American factories hummed at a feverish clip". Real GDP grew over one-third during Reagan's presidency, an over $2 trillion increase. The compound annual growth rate of GDP was 3.6% during Reagan's eight years, compared to 2.7% during the preceding eight years. Real GDP per capita grew 2.6% under Reagan, compared to 1.9% average growth during the preceding eight years. In nominal terms, median household income grew at a compound annual growth rate (CAGR) of 5.5% during the Reagan presidency, compared to 8.5% during the preceding five years (pre-1975 data are unavailable).