Asking Spragg would be more on target. "Turnover" is a British financial term for what we (Americans) would call "Total Revenue" or gross revenue.
Macao & Hong Kong would use these terms given their commercial heritage.

Definition from a financial dictionary:
Total revenue
Total sales and other revenue for the period shown. Known as "turnover" in the U.K.

As for the "rolling" part, note that it speaks to a most recent MONTHLY statistic, then refers to year-over-year increase. A "rolling" annual amount would take the most recent month, say May 2012, plus the 11 prior months, back to June 2011, to make a "rolling" year. Next month, the rolling year would drop off the oldest month, add the newest month, and make an updated rolling year of July 2011 thru June 2012.

When comparing the most recent rolling year (12 months) with 12 additional preceding months, you have a year-over-year comparison of two 12-month periods: June 2011-May 2012 vs. June 2010 vs. May 2011.

In the context of the article, the "chip" part probably refers to gaming (table) revenues.

So, in translation this company (AERL) is bragging that their gaming revenues went up 14% in the most recent 12-month period, compared to the same period of a year prior. And their 14% increase beat the overall Macao gaming increase of 7%.