You are planning to sell chocolate on Valentine's day. Based on historical demand, you estimated that the chocolate demand on Valentine's day follows a normal distribution with a mean of 185 and a standard deviation of 19 boxes of chocolate. You pay $6 for each box, which sells for $26. Any leftover box of chocolate can be sold for $2 the following day. According to this given information, what is the optimal number of chocolate boxes to order for the Valentine's day sale.