Changing the old url! Where's my PageRank?

Long time no see, guys. I got trouble with my website. When i didn’t know too much about web design or coding, I made a html page that have hyphens like this:

My subpage has PR 3!

I decided to change the url hyphens as google guide to this:

And … it goes down to zero ( PR 0 ) …

I’m confused pros please help me out of this!

Any help is appreciated!

P/S: Please move my question if i was wrong location. Thanks Mods!

[font=verdana]How have you told search engines that the URL has changed – did you use a 301 redirect?

There are three outcomes after you change the URL of a page:

[list][]the old URL is automatically redirected to the new one – good, this means that search engines will (in time) update their indexes, replace the old URL with the new one and transfer all the rankings and ratings across. This may take a little while, especially if you have a low crawl rate.
]the old URL goes to a 404 error – bad, this means that search engines (and people following old links) will be aware that the page has gone, but there is nothing to help them find the new page, so it can take a lot longer before the old URL is removed and the new URL gains credit and works its way up the ranking, especially if there are lots of links out there pointing to the old URL.
[*]the old page is still there at the old URL - really bad, this means that search engines won’t know that the page is out of date and has been replaced, so will continue to be indexed.[/list]

But it really isn’t worth worrying about your PageRank … what matters is whether your site appears high up the rankings for relevant queries. If the answer to that is “yes” then you can happily ignore your PR![/font]

Thank Stevie D! I didn’t use the 301 redirect… I will try and report the result after i added.