Yahoo spam mail more than gmail

Most of the times when I first login into my yahoo and gmail mailbox, I will delete all the spam mails first. Those mails taking up lot of my space and I dislike to see so many unread mail in my mailbox too! Another my finding is I noticed my yahoo spam mails is a lot more than my gmail account. Most bloggers told me those spam mail will be a lot after you use them for your paid post corresponding. But for my yahoo, it is all the time having lot of spam mail even before I wrote for any paid post. Just wonder how they reach me. Most of the items offer to me is those Viagra thingy. In a day, I can get at least 10-20! *faint**sigh*

My gmail spam mail still manageable, daily is about 5-10. Some times geinuine mail will go to spam too, have to go through before I selecting all and press delete.