---
title: "Best month and worst month"
description: "Best month and worst month are the highest and lowest single-month returns a strategy recorded over its backtest, shown as two rows in the metrics table."
canonical_url: "https://fincanva.com/docs/analysis/best-month-and-worst-month"
last_updated: "2026-07-25"
md_url: "https://fincanva.com/docs/analysis/best-month-and-worst-month.md"
---

# Best month and worst month

Best month and worst month are the highest and lowest single-month returns a strategy recorded over the backtest period. The [metrics table](/docs/analysis/metrics-table) lists them as two separate rows, "Best month" and "Worst month", in the **Monthly performance** group. Each is one month out of the run — the single strongest and the single weakest — so together they mark the extremes of the monthly return series without you having to scan every month.

**Also seen as:** biggest monthly gain, biggest monthly loss, monthly extremes

## How are best month and worst month measured?

Both are read off the same month-by-month return series: best month is the largest value in that series and worst month is the smallest. No averaging or smoothing is involved, and neither figure is combined with its neighbours — a month that gained 12% is the best month even if the months either side of it lost ground.

## Is the worst month the same as max drawdown?

No — the worst month is one calendar month's return, while [max drawdown](/docs/analysis/max-drawdown) is the largest peak-to-trough fall of the capital curve. A drawdown can start mid-month, run across several months, and end mid-month, so it is usually deeper than the worst single month and always measured from a peak rather than from a month boundary. A strategy can have a mild worst month and a severe max drawdown if the losses were spread out; how long such a decline lasted is [longest drawdown](/docs/analysis/longest-drawdown).

## What counts as a good value?

The pair is read as a range rather than as two separate scores: a narrow gap between best and worst means month-to-month outcomes clustered together, and a wide gap means they were spread far apart, which is the same behaviour [volatility](/docs/analysis/volatility) puts into a single annualized number. A high best month is not evidence of a better strategy on its own — a single outsized month can lift a whole run's [total return](/docs/analysis/total-return) while the other months contributed little, and the [monthly average](/docs/analysis/monthly-and-yearly-average) beside it is what shows whether the rest of the period pulled its weight.

## Defaults in Fincanva

- Both appear as rows in the **Monthly performance** group of the metrics table, labelled "Best month" and "Worst month", as percentages to one decimal place and coloured by sign.
- The monthly returns view repeats them as KPIs using the same two labels.
- They come from the same month-by-month series the [monthly returns heatmap](/docs/analysis/reading-the-monthly-returns-heatmap) displays, so you can find the two months on the grid.
- Each is a single calendar month of the simulated period — never a rolling 30-day window and never a run of consecutive months.

## Worked example

A ten-year backtest reports Best month +12.0% and Worst month −18.0%. Those are two individual months out of roughly 120, and the 30-percentage-point spread between them tells you monthly outcomes ranged widely. The −18.0% month is not the run's max drawdown: if the strategy also fell in the month before and the month after, the peak-to-trough decline around that month is deeper than 18%. Equally, the +12.0% month may be the reason the run's total return looks strong, which is why the monthly average is worth reading next to it.

*Best month and worst month describe what a strategy would have done on historical data, not what it will do. Fincanva provides no financial advice — see [Is this financial advice?](/docs/investing-theory/is-this-financial-advice).*