# How to Analyse the Profit Margin on Coal Burnt at a Station

This guide will show you how to use the coal burnt and spot revenue data in NEM-Review to trend the "average revenue per tonne of coal burnt" for any station.

There are two key steps:

- In NEM-Review: Trend the monthly revenue and coal burnt for a station
- In Excel: Use this data to calculate the monthly average revenue per tonne

## 1. Trend monthly revenue and coal burnt

- Open your NEM-Review Analysis Client
- Click the
**Trending Graph**button - In the
**Date Range**selector, select from 1 August 2009 to 31 July 2010 (or any other date range that encompasses a series of full months). - In the
**Data Series**selector, tick*Spot Revenue*and*Coal Burnt*for the station you are interested in. - In the
**Data Series Editor**, set the resolution to**Monthly**and the Aggregation to**Total**. - Click the
**Graph View**button to take a look at the graph. - Click the
**Table View**button to view the data behind the graph.

*Note the significant increase in revenue over the summer months, independent of the amount of coal burnt.*

## 2. Calculate monthly average revenue per tonne of coal burnt

- Still in table view, click the
**Hide Formatting**button to show raw data without units or rounding. - Select the entire table by clicking in the grey space in the
**top left corner of the table**(just left of the column headings). - On your keyboard, press and hold
**Ctrl**then**c**at the same time to copy the data to your clipboard. - Open a new Excel spreadsheet, and paste the data into it (press
**Ctrl+v**or right click a cell and select**Paste**). - In column D we will convert the coal burnt from
**kg**to**tonnes**. - In column E we will calculate the
**monthly average revenue per tonne coal**. - If you wish, you can format your data and create a graph using Excel.

Note that the unformatted coal burnt data is in **kg**.

Column A should be the Settlement Date, column B the Spot Revenue, and column C the Coal Burnt. The first row will contain the column headings.

In cell D2 enter the formula **=C2/1000** (divide the value in column C by 1000). Copy this formula to the rest of the cells below in column D.

In cell E2 enter the formula **=B2/D2** (spot revenue / tonnes coal burnt). Copy this formula to the rest of the cells below in column E.