Explain the Possible Causes of the Trends in the Following

Essay

Explain the possible causes of the trends in the following data:
$$\begin{array} { | l | r | r | r | } \hline & \text { Year 1 } & \text { Year 2 } & \text { Year 3 } \\\hline \text { Gross profit margin } & 35 \% & 31 \% & 28 \% \\\hline \text { Operating profit margin } & 9 \% & 11 \% & 13 \% \\\hline \text { Net profit margin } & 4 \% & 19 \% & 7 \% \\\hline\end{array}$$