AstraZeneca: Vaccine Averaged 70% Effectiveness

AstraZeneca's vaccine candidate shows up to 90% efficacy with a specific dosing regimen, but averages 70% when combined with another regimen. AstraZeneca is the third major company to report high efficacy, following Pfizer and Moderna, whose vaccines are nearly 95% effective.

What is the significance of Astra Zeneca being the third major company to report its vaccine results?

Which other companies reported vaccine efficacy rates close to 95% just before Astra Zeneca?