All the data was obtained from the American Community Survey 1-year conducted by The United States Census Bureau. The data was yearly and the income data has different categories including Household, Family, and Coupled-family. We only use the household income data since it is more inclusive, and can capture a wider range of economic situations.  

Link to Data

The upper map shows the median household income. We used the median income to show the economic overview.  The median provides a better indicator of the central tendency for skewed distributions. By selecting through the year, we can tell most of those high household incomes are from North CA around Bar Area which is around San Francisco. 

The lower left graph reflects the percentage of a specific county’s median income changes compared to California's average percentage of median household income changes. This will reveal if the county’s economic growth is above or below the average of growth over California. We noticed that there is a dramatic decrease in the change of CA's average household income, we believe that the economic downturn was caused by the first coronavirus‐related activity restrictions that were issued on March 12, 2020.

The lower right graph shows the contrast between mean and median household income. Income distribution can be highly unequal. Most of the data from different countries show that the figures of  Mean and Median household income are diverging.