Extracted the numbers from the article, which is in prose instead of table form. It looks like most of these numbers are estimates from William Blair[0], not Amazon itself.
Gross margins by service:
* EC2: ~50%
* S3: 50-70%
* EBS: 60-70%
* Aurora: 65-75%
* Bandwidth: 99%
* AWS Marketplace: >30%
[0] https://www.williamblair.com/