code: public int getDocumentsPerPage() {
      try {
        final int perPage = _jsonObject.getJSONObject(META_OBJECT_FIELD).getInt("per_page");
        return perPage;
      } catch (JSONException ex) {
        throw new QuandlRuntimeException("Could not find total_count field in results from Quandl", ex);
      }
    }
docs: Get the number of documents per page in this result set. Throws a QuandlRuntimeException if Quandl response doesn't contain this field,
  although it should.
  
  @return the number of documents per page in this result set