Unsubscribe rate. Unsubscribes are always going to happen no matter what, and that’s usually OK because those people probably would never have bought from you anyway. However, a high unsubscribe rate can indicate that you are losing potential customers. Check the following: Why did people subscribe to your list in the first place, and are you delivering on that promise? Is the content of your autoresponder highly relevant to the segment it is being sent to? Are you sending too many sales emails with too little value emails? (Recommended reading: 5 Reasons Why People Unsubscribe from Your Email List.)
3) I would then set up List Builder from SumoMe on blog pages. Noah Kagan and his group at AppSumo have put together this awesome little pop-up tool that will show over the center of your screen asking you to sign-up, or you can easily click outside of the box to cancel it out. The thing is, initially all of my clients would say “I don’t want a spammy pop-up on my site, people will hate us!” But truly this has had tiny effects on bounce rates (meaning people aren’t really leaving because of this, they’re simply clicking the box away) yet they’ve had a massive effect on subscriber sign ups. List Builder also integrates with MailChimp, so all of these 3 tools work seamlessly together.

GT STRUDL has offered structural engineers a complete design solution, and we've now incorporated 3D CAD modeling and 64-bit high-performance computation solvers into all versions. The structural analysis software is a high-quality, fully-integrated, database-driven system for comprehensive frame and finite element analysis and steel and reinforced concrete design