· S.H.I.E.L.D was the #1 scripted series in its hour among Men 18-34 for its 19th-straight original telecast. S.H.I.E.L.D. is Tuesday's #1 TV show this season with Men 18-34 and Men 18-49.
· S.H.I.E.L.D. improved its hour by 64% for ABC year to year in Adults 18-49, over the year-ago night with original programming.
This is why I don't see a problem with it getting renewed. It's not the mega-hit that you'd expect a MCU tie-in to be after the Avengers (nor is it critically acclaimed for the most part), but it's something that will continue making ABC money with the only demographic that really matters for a show like this.
Only way it is getting canceled is if Disney/Marvel just have no idea where to go with it next season as they prepare for the end of phase 2 with AoU and Ant-Man. In other words, creative reasons instead of it just being a massive disappointment to ABC.