This is the last of a six-part series on how your business can get started on YouTube. In this installment, we examine how to track the performance of your YouTube videos.

Uploading a video to YouTube is just the start of a continuing process. You need to measure the effectiveness of each of your videos to learn how you can improve the next one.

YouTube provides its own performance-tracking tool that examines the key metrics for all videos on its site. YouTube Analytics puts some of the most important metrics right on the video viewing page. More detailed metrics are presented when you click the Analytics button beneath each video.

Here are five things you'll want to do when tracking the performance of the videos you post to your company's YouTube page:

1. Track views.
The first metric marketers look at is also the most basic: how many people have viewed your video in a given period of time. YouTube also lets you analyze the demographic composition of those views, by gender, age and location.

How many views is a good number? It depends on your goals. If your video gets a million views overnight, that's the sign of a viral video. But not every business needs or wants such huge viewership. For certain types of videos and businesses, a total of 100 views might be good -- as long as they're from your targeted audience. You have to judge performance based on your own parameters, and with realistic expectations.

2. Track traffic sources.
You can more effectively promote your videos if you know how viewers found them. They can be linked to from other videos, searched for on the YouTube site or connected through another source.

For example, if you find that the majority of viewers discover a video by searching on YouTube, you know you need to optimize future videos for search. YouTube Analytics can help you by showing the keywords that were searched for, so you can include the most popular ones in the descriptions of subsequent videos.

You also can use the traffic sources metric to determine why a particular video didn't perform well. Look at how viewers did -- or more important, didn't -- find the video. If, for example, a video didn't pull well via search, then you know you need to pay more attention to keywords in future video descriptions.

3. Track engagement.
Merely viewing a video isn't enough. You want viewers to engage with it, talk about it and share it with friends.

To help you monitor engagement, YouTube offers a number of different reports. You can track how many people subscribe to your YouTube channel, how many likes and dislikes a given video received, how many people have given it a "favorite" tag, how many comments were received about it and how many times it was shared on Facebook, Twitter and Google+.

The greater the level of engagement with your video, the better you're connected with your customers and the more word-of-mouth promotion they're likely to provide.

4. Track audience retention.
Just because someone starts a video, it doesn't mean he or she will watch all the way through. Audience retention is an important metric showing how long, on average, viewers watch each video and when they lose interest and tune out.

YouTube's audience retention metric lets you see viewership on a second-by-second basis. It's a useful tool for fine-tuning your videos and producing ones that pack a punch from beginning to end.

If you find that most of your viewers are watching only the opening moments of your video, you know you're not grabbing them. If a large percentage of viewers quit watching at a later point in the video, you can try to determine what turned them off at that juncture.

5. Track conversions.
YouTube Analytics can't help you here. You will have to examine the number of conversions a video generates on your own linked-to website.

The conversion metric, of course, depends on what type of response you want. Is the video designed to generate sales, or is it meant to drive traffic to your website? If you hope to boost revenue, you would simply measure how many sales you made to video viewers who linked to your site. You might find that a video with a relatively small viewership actually delivers a higher conversion rate -- and that's true success.