Instruction 14-3
the Number of Cases of Merlot Wine Sold

Instruction 14-3
The number of cases of merlot wine sold by a Barossa Valley Winery in an eight-year period follows.
$\begin{array}{ll}\text { Year } &\text { Coses of }\\& \text { Wine } \\2003 & 270 \\2004 & 356 \\2005 & 398 \\2006 & 456 \\2007 & 358 \\2008 & 500 \\2009 & 410 \\2010 & 376\end{array}$


-Referring to Instruction 14-3,a centred three-year moving average is to be constructed for the wine sales.The moving average for 2004 is _______.