The colon is used to separate two independent clauses when the second explains or illustrates the first. In such usage, the colon functions in much the same way as the semicolon. As with the semicolon, do not capitalize the first word after the colon unless the word is ordinarily capitalized.
The median household income in 2014 was $53,719, which means that half of American households make less than this amount, and half make more. Since the median is significantly below the average, it tells us that there are more households with below-average household income than above-average, and that the average is distorted by a small percentage of high-income households.
Compared to the median US household income, California median household income is $8,276 higher. 2015 Census ACS data (including 2015 California household income numbers) will be released in September of 2016. California median family income and per capita income for California are shown further down.