As an investor, today you are taking following portfolio:

1. Short-sell a non-dividend paying stock that has a current price $24$24.
2. Sell a collar on the same stock

Under the following assumptions:

• All options will expire in 11 year.
• Premium for 2020-strike call and 3030-strike call options are $6$6 and $2$2, respectively.
• Premium for 2020-strike put and 3030-strike put options are $1$1 and $5$5, respectively.
• The continuously compounded risk-free interest rate is 3%.
• Transaction cost is zero.

The maximum profit of this portfolio at the expiration time is (please use 1 decimal place)