docker stats CPU, Cores, %s

I ran docker container on host with 3 cpu cores.. when i use: docker run -it -d --cpuset-cpus="0" the containers can use 100% of CPU..

but when i use docker run  without --cpuset-cpus, the container consumes 900% of CPU. The correct 

it should be 300%, shouldn't?

is there a mistake in cpu usage calculation?

docker info

Server version 1.10.3

CPUs 3
