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In this lesson,

we are going to learn about an important concept in agile planning called velocity.

To learn about velocity, let's take an example.

Let's say, you are in a new country and you are on a road trip

from point A to point B which is about 300 miles apart and

I ask you how long will it take you to go from point A to point B?

You may answer like I don't know what kind of roads are going to be.

What kind of traffic it is.

So come back after and hour or two, and

I'll tell you how long it's going to take me.

So after you have driven for awhile,

let's say in the first hour you covered 50 miles.

And in the next hour, you covered 45 miles.

So if I come after two hours and I ask you,

how long do you think now it'll take you to reach to point B?

You may say, well, it's 40, 50, 45.

Approximately, I'll say, 50.

Ad so, it'll take me and I have driven for two hours.

So I think it's going to take me another four hours.

So, my velocity is approximately 50 and I have another 200 miles to go.

So, it's about four more hours.

Similar concept is used in agile planning.

So, velocity is amount of work that a team.

So, it's about team.

A team is getting in a sprint.

And then again, then it depends on the team or the project.

For example, in your case, the road matters, the traffic matters or

the people who are in your car matters.

So if you have kids, you might take more breaks.

And if you are just single, then you might just go faster and

you don't did as many breaks.

So again, it depends on a lot of factors.

But whatever is the team velocity is what we use.

So, how do we calculate velocity?

So to calculate the velocity for a sprint that you just finish, let's say,

you just finish the sprint and you want to calculate the velocity for that sprint.

You basically take all the stories that you finished.

Let's say, you finished three stories with estimate of five, three and ten and

you add them together.

So in this case, it's going to be the velocity for

that sprint is going to be 18.

Now, velocity is also used for predicting or

selecting stories for an upcoming sprint.

So let's say, you just finished as you can see in the table here,

the sprint 21 to 27 and their velocity.

So let's say, you are about to start the sprint number 28 and

you want to know what velocity you should use to pick the number of story for

a sprint 28, then there are several ways you can do.

The first one very simple.

You may say, well, I'm just going to use the velocity of the last sprint always.

So if I'm doing a sprint 28, I'll just use the sprint, the velocity for sprint 27.

So in this case, if I use that technique, I'll just use the velocity of sprint

27 which is 23 and that's what I'll use for sprint 28 for planning.

The another concept you can use is average of last x sprints.

So in this case, if I use the last three sprints,

then the predicted velocity or the velocity that I will use for

planning in sprint 28 will be the average of sprint 25, 26 and 27.

So the velocity for sprint 25 is 25, 26 is 27 and then for sprint 27 is 23.

So I add them together and take an average, it comes out to be 25.

So for sprint 28, I will take stories worth 25 points.

The third style of calculating velocity is the velocity range.

So in which, you calculate the minimum and

the maximum velocity for the last x sprints.

So in this case, if I was using the last three sprints,

then to calculate the velocity range for spring 28, I will be using spring 25,

26 and 27 and the minimum is 23 and the maximum is 27.

So, I will be using the minimum is 23 and 27.

So, the range is going to be 23 to 27.

Now if you look at sprint 23, you see the velocity of 54.

That sounds like anomaly.

So unless it was pretty natural, they must have something special or

something has happened.

But in this case, you would escape that velocity.

So in case I was using the last five, if my method was to use the last

five sprint for calculation, I would skip sprint 23.

Now, there are several situations that you will encounter as you will use velocity.

So, let's take some of those situations that you in which you may have to adjust

your velocity or not.