spotPrice

The maximum hourly price to be paid for any Spot Instance launched to fulfill the request. Spot Instances are launched when the price you specify exceeds the current Spot price. For more information, see Request Spot Instances for fault-tolerant and flexible applications in the Amazon EC2 Auto Scaling User Guide.

Valid Range: Minimum value of 0.001

When you change your maximum price by creating a new launch configuration, running instances will continue to run as long as the maximum price for those running instances is higher than the current Spot price.