here is a nice and easy way to make  fading text just like this.

1. create a new file

2. type your text with the text tool

3. choose your text and click modify, break apart

4. create a couple of frames by going to the frame number and right click, insert keyframe (here I used 10 frames)

5. go to the first frame, choose all the text and press F8 and choose graphic as the symbol (this will convert the text to a graphic symbol)

6.double click the graphic you just made, go to the color tab

7. in the color tab choose alpha as the color effect and move the percentage to %0.

8. now right click the first frame and choose create motion tween.

9. choose your graphic in the first frame and copy it by pressing ctrl + c or by clicking edit, copy

10. go to the last frame and paste the graphic by pressing ctrl + V or by clicking edit, paste

11. choose your graphic in the last frame and double click it.

12.go to color, and move the percentage back to %100

13. your done , you now have a fading text