Thanks for you inquiry. In terms of the figures provided in your email, the heading outlines that they relate to "Common assault of an emergency worker, Scotland 2013-14 to 2015-16."
Common law assault is a different crime to the statutory offences under section 1(1) and 2(1) of the Emergency Workers (Scotland) Act 2005. From your email it is not clear in the figures you have gathered from the Scottish Government what the terms "common assault" or "emergency workers" cover nor is it clear whether the figures provided relate to the number of incidents, individuals or charges recorded by the Police or reported by the Police to COPFS in those calendar years.
The figures included in the answer to the Parliamentary Question provided by the Lord Advocate to the Scottish Parliament relate specifically to the number of charges under sections 1(1) and 2(1) of the Emergency Workers (Scotland) Act 2005 which were reported to COPFS by the Police in those financial years.
The only comment I can helpfully make about the difference between these two numbers is that they appear to reflect two different categories of offences and so it is not possible to make any assessment about a drop between the two.