# Add a trendline or note to a chart

You can add trendlines to see patterns in your charts. You can also add a note, or annotation, to explain trends or observations.

## Add or edit a trendline

Trendlines work when the horizontal (X) axis has numbers. You can add trendlines to:

- Scatter plots
- Line charts
- Column charts
- Bar charts

To add a trendline:

- On your computer, open a spreadsheet at sheets.google.com.
- Double-click a chart.
- In the side panel, click
**Customize****Series**. - Check the box next to "Trendline." If you don’t see the trendline option, it means trendlines don’t work with your data.
- Choose your trendline options. Your changes will be automatically saved.

Trendline options

### Trendline types

**Linear**: For data that closely follows a straight line. Trendline equation: y = mx+b.**Exponential**: For data that rises and falls proportional to its current value. Trendline equation: y = A*e^(Bx).**Polynomial**: For data that varies. Trendline equation: ax^n + bx^(n-1) + … + zx^0.**Logarithmic**: For data that rises or falls at a fast rate and then flattens out. Trendline equation: y = A*ln(x) + B.**Power Series**: For data that rises or falls proportional to its current value at the same rate. Trendline equation: y = A*x^b.**Moving Average**: This helps smooth out data that is unstable or more variable.

### More options

You can edit these features:

**Line color****Line opacity****Line thickness****Label****R squared**to show how closely the trendline fits the data. The closer to R^2 = 1 (or-1), the closer the fit. This feature is only available if you add a label.**Polynomial degree**(available for polynomial trendlines)**Average type**(available for moving average trendlines)**Period**(available for moving average trendlines)

## Add notes to a line or area chart

Add notes to a data point

- On your computer, open a spreadsheet at sheets.google.com.
- In the column to the right of each data point, add your text notes.
- Your notes will show up on your chart.

### Example

**Column A**: Labels for horizontal (X) axis**Column B**: Data points for vertical (Y) axis**Column C**: Notes

1 | A | B | C |
---|---|---|---|

2 |
Day of Week |
Sales |
Notes |

3 |
Monday | 50 | Low profits |

4 |
Tuesday | 100 | Online coupon announced |

Add notes to the horizontal axis

- On your computer, open a spreadsheet at sheets.google.com.
- To the right of the column with your X-axis, add your notes.
- Your notes will show up on your chart.

### Example

**Column A**: Labels for horizontal (X) axis**Column B**: Notes**Column C**: Data points for each label

1 | A | B | C |
---|---|---|---|

2 |
Day of week |
Notes |
Sales |

3 |
Monday | Low profits | 50 |

4 |
Tuesday | Online coupon announced | 100 |