However, under certain circumstances, payment for personal services performed in the United States is not considered income from sources within the United States. For example, personal services performed by an independent nonresident alien contractor specifically exempted by a tax treaty. For more examples, see the Pay for Personal Service section in Publication 515, Withholding of Tax on Nonresident Aliens and Foreign Entities.
Seven of the ten counties in California with the lowest per capita incomes are located in the Central Valley. Two of the remaining three are rural counties in Northern California. This leaves Imperial County, which shares California's portion of the U.S.-Mexico border with San Diego County. All of these counties had populations not exceeding 1,000,000, and all of them are landlocked, with the exception of Del Norte County.

Most of us think of investment income as just the cash flow we get from bank interest, bonds, share dividends and property rents, some of which comes via a super pension.  But a more complete view is to also consider how growing the value of your investments can add to your spending potential.  This total return approach generates income from both income and growth to optimise spending from your portfolio across all market cycles, aligning cheap and expensive investments to your goals.