Problem with JSON-structure: check basenode-param

Apologies in advanced if this is basic 🙂

I have added the following to a Test Page in WP:
[jsoncontentimporter url=”https://api.blockchain.info/charts/transactions-per-second?timespan=5weeks&rollingAverage=8hours&format=json” numberofdisplayeditems=”-1″ basenode=”values”]

• {y} <hr>

[/jsoncontentimporter]

this is the error message:
“neither object nor array? not implemented yet and underneath
“Problem with JSON-structure: check basenode-param”

I just want values (that’s the basenode) and {y} node, see example of url JSON Format return on the above URL below:

{
  "status": "ok",
  "name": "Transaction Rate",
  "unit": "Transactions Per Second",
  "period": "minute",
  "description": "The number of Bitcoin transactions added to the mempool per second.",
  "values": [
    {
      "x": 1485457620,
      "y": 3.847395833333335
    },
    {
      "x": 1485459600,
      "y": 3.8571527777777783
    },
    {
      "x": 1485461580,
      "y": 3.8817013888888905
    },
    {
      "x": 1485463560,
      "y": 3.866805555555558
    },

etc . Thank You