PHP Question For a GURU

[sobitcoin]

Hello! I have a PHP question that has been stumping me for the last 24 hours and I think someone who knows what they are doing would have a simple answer. 

If this is returning single values for an exchange

Code:

$btcbtcchinaPrice = $btcbtcchinaUSD["ticker"]["last"];
$btcbtcchinaVol = $btcbtcchinaUSD["ticker"]["vol"];

How would I change those tags to return all values under certain rows on this api

http://api.bitcoincharts.com/v1/markets.json


I just cant figure out the way to write the selectors, everything i try gives errors 

[1715127470]

1715127470

[1715127470]

1715127470

[1715127470]

1715127470

[1715127470]

1715127470

[gweedo]

You have to use a loop.

[sobitcoin]

You have to use a loop.

Damn loops. They never go away go they.