A significant point of confusion for those outside the aviation industry is that flight attendants are typically only paid for "block time." This means their hourly wage starts when the aircraft door is closed and the brakes are released, and it stops once the door is opened at the destination. Consequently, they are often not paid for the hours spent commuting to the airport, clearing security, or even the intense and stressful boarding process, though Delta Air Lines made history recently by implementing "boarding pay" at half their regular rate. Most flight attendants "fly" between 75 and 85 block hours per month, but their actual "on-duty" time can be double that. In addition to block pay, they receive a "per diem," which is a small hourly amount (typically $2.00 to $3.00) meant to cover meals and expenses while away from home. While the hourly rate might look high (e.g., $40/hour), the fact that they only get paid for roughly 80 hours a month means their total monthly take-home pay is often more modest than people expect, especially in the first few years of their career.