What you need to know about the minimum wage

This is life on $7.50 an hour
This is life on $7.50 an hour

Nationwide, 9.3% of U.S. workers make at or near their state's minimum wage, according to estimates from the Economic Policy Institute.

That 9.3% includes people who actually make less than the minimum wage, because they're among the groups of low-wage workers who aren't protected by minimum wage laws, such as the disabled and teenagers.

Most states have minimum wages above the federal level

The federal minimum wage has not increased since 2009 and is currently set at $7.25 an hour. But 29 states and D.C. have higher minimums.

For tipped workers, the federal minimum wage is $2.13 -- 18 states use this rate; the other 32 set a higher minimum wage for tipped workers.

Some states are going even further

Since 2012, workers have staged strikes and demanded a living wage as they "Fight for $15." In the U.S., more than 40% of all workers earn less than $15 an hour.

Meanwhile, California became the first state to adopt a statewide $15 minimum wage on Thursday. It will increase gradually from $10 today to $15 by 2022 for most businesses. Assuming 1.5% annual inflation, $15 in 2022 is about $13.72 today. Nearly 2.2 million workers in California currently make the minimum wage.

Also on Thursday, New York reached a deal to hike its minimum wage. Governor Andrew Cuomo proposed a 67% increase from $9 an hour to $15 over the next several years. The increase was included in the annual state budget. Over 2.3 million people are expected to be affected by the increase.

Some cities have their own minimum wages

Around the country there are 22 cities and counties that have minimum wages that are higher than their state's levels. Among them are Albuquerque, New Mexico, Louisville, Kentucky and Emeryville, California. At $14.14 an hour, Emeryville's minimum wage is currently the highest in the country.

North Carolina and Alabama have recently passed laws to keep their cities from raising the minimum wage.

Birmingham, Alabama had voted to raise its minimum wage to $10.10 an hour. But that was struck down before it could take effect when Alabama passed a law preventing cities from enacting their own minimum wages.

Several cities and counties in North Carolina had minimum wages that were higher than the state's $7.25 an hour. However, last week the state enacted a law striking them down.

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