https://blockchain.info/charts/hash-rate

Have I missed something ?

Hello,

I follow the steps I found here , trying to understand how things works.
But I can't understand why when I copy/paste the extended key from step 2 (800C28FCA386C7A227600B2FE50B7CAE11EC86D3BF1FBE471BE89827E19D72AA1D)  to this on-line calculator , I can't take the result of step 3.
What I'm  doing wrong ?

Thanks in advance.