What is Throughput?
Throughput is the total number of items completed per unit of time. You might have a throughput of 2 per day, 10 per week, or even 17 per sprint. Whatever your preferred time time unit, this flow metric helps you understand how quickly you finish work. That understanding is critical for forecasting how long it will take to complete a collection of work items.
There are two things you need to define to calculate throughput:
- Your Finish Line – or the point in your process that items are considered complete
- Your Time Unit – day, week, month, etc.
Defining the Finish Line
In order to define a finish line, you have to understand your process. A Kanban board is a great way to do visualize your process and make sure that it is clearly understood by all. Take a look at the board below:
This team has defined the Done column as their finish line. So, any items that move into the Done column are counted as Throughput.
Defining the Time Unit
You can use any time unit you desire to measure throughput. You can measure per day, per week, per month, per Sprint – you get the idea.
In ActionableAgile, we default to day for the time unit. In certain charts you have the option to choose from day, week, or month. But, in our forecasting simulations, we always use day as our time unit as that is the most flexible.
Why should I use Throughput?
Looking at your Throughput allows us to analyze how consistently you deliver value. Consistency of throughput, and how it compares to the rate at which you start work, is one indicator of how stable your process is.
Perhaps the most common use for the Throughput metric is to aid in providing forecasts for completing multiple work items. You can use Cycle Time to forecast for single items, but you need a rate metric like Throughput to provide forecasts for groups of work items. Keep reading to learn how to analyze and use Throughput in ActionableAgile.
Throughput charts in ActionableAgile
There are two Throughput charts available in ActionableAgile: a histogram and a run chart.
The Throughput Histogram is a bar chart that displays how often you experience certain daily Throughput – in other words, the frequency of Throughput values.
The Throughput Run Chart is, hands down, the best chart to use because of the time axis. We believe that all time-based metrics are best analyzed on a time-based chart. This allows you to see patterns in your data and ask questions to learn more about how your team worked and why. You cannot discern this pattern-based information in a histogram.
Using Throughput to forecast
Traditionally, people use their Throughput to determine an average rate at which work is finished and then divide the total work by that average. However, forecasting based on averages will produce average results. Instead, our Monte Carlo simulations use the data in the Throughput run chart to simulate probable outcomes based on the variation found there. It’s a much more accurate, not to mention risk-aware, way to deliver forecasts. Read more about our two Monte Carlo simuations:
- Monte Carlo: How Many – provides forecasts for how many items you are likely to finish in a set period of time
- Monte Carlo: When – provides forecasts for when you are likely to finish a set number or range of items
Teams often start looking at Throughput around the same time they begin looking at Cycle Time, WIP, and WIP Age. Focusing on building stability in these key flow metrics is a good start. The more stable your basic metrics are, the fewer outliers your forecasts have to account for and the more your forecasts are perceived as acceptable and, most importantly, accurate.