weightedCapacity

The number of units provided by the specified instance type. These are the same units that you chose to set the target capacity in terms of instances, or a performance characteristic such as vCPUs, memory, or I/O.

If the target capacity divided by this value is not a whole number, Amazon EC2 rounds the number of instances to the next whole number. If this value is not specified, the default is 1.

When specifying weights, the price used in the lowest-price and price-capacity-optimized allocation strategies is per unit hour (where the instance price is divided by the specified weight). However, if all the specified weights are above the requested TargetCapacity, resulting in only 1 instance being launched, the price used is per instance hour.