``\pi= \frac{P_t-P_{t-1}}{P_{t-1}} \[{}\pi= \frac{P_t-P_{t-1}}{P_{t-1}} {} \]
\pi= \frac{P_t-P_{t-1}}{P_{t-1}}
You can also embed plots, for example:
Note that the echo = FALSE parameter was added to the code chunk to prevent printing of the R code that generated the plot.
echo = FALSE