To figure out how many vacation days she had left to use, Jenna looked over her calendars to figure out how many days of vacation she had taken each year.
\begin{tabular}{|c|c|}
\hline \multicolumn{2}{|c|}{ Vacation days taken by Jenna } \\
\hline Year & Vacation days \\
\hline 2009 & 35 \\
\hline 2010 & 42 \\
\hline 2011 & 42 \\
\hline 2012 & 34 \\
\hline 2013 & 32 \\
\hline
\end{tabular}

According to the table, what was the rate of change between 2011 and 2013? vacation days per year

Step 1 ：Jenna looked over her calendars to figure out how many vacation days she had taken each year. The data is as follows: \n\n\begin{tabular}{|c|c|}\n\hline \multicolumn{2}{|c|}{ Vacation days taken by Jenna } \\ \hline Year & Vacation days \\ \hline 2009 & 35 \\ \hline 2010 & 42 \\ \hline 2011 & 42 \\ \hline 2012 & 34 \\ \hline 2013 & 32 \\ \hline\n\end{tabular}

Step 2 ：We need to find the rate of change between 2011 and 2013. The rate of change between two years can be calculated by subtracting the number of vacation days in the first year from the number of vacation days in the second year, and then dividing by the difference in years.

Step 3 ：Subtract the number of vacation days in 2011 from the number of vacation days in 2013: \(42 - 32 = 10\)

Step 4 ：Then divide by the difference in years (2013 - 2011 = 2 years): \(10 \div 2 = 5\)

Step 5 ：However, since the number of vacation days decreased over the years, the rate of change is negative. So, the rate of change is \(-5\)

Step 6 ：Final Answer: The rate of change between 2011 and 2013 was \(\boxed{-5}\) vacation days per year.