Over the course of the last year there have been many changes to the Google algorithm which have made it more difficult for SEO tracking. Essentially, the complete integration of a local 3 pack into results, as well as the localization of the universal results delivered below it, have made it exceedingly difficult to track the actual positions that are delivered outside the local area of the tracking computer. This means that if your business wants to rank all over the country for a specific term, you will probably not be getting true results for areas outside of your locality anymore due to the removal of the “area” functionality from Google. Obviously this was done because not enough regular users found it valuable, and it was only being used by SEO services companies. Why would a regular person care about a search phrase ranking outside of a local environment, unless they were tracking global results? Anyway, the takeaway is that if you are looking for results globally and are searching from Las Vegas for a business based in Las Vegas, you are probably not seeing the same things as someone in Boston.
Location based search used to be able to be checked by changing the city in Google away from the default area, which used your IP address to fix your position. Now that this feature is removed, IP address dictates all searches to a certain degree, even if you geotarget the search with a city name. While this makes it difficult for SEO firms to accurately track results, it is probably more valuable to actual customers. There are several tools available which can provide less filtered results to your searches, mostly embedded into tracking software systems but some available as standalone products online. Our favorite is http://isearchfrom.com/ which provides a user the ability to search from a country standpoint, filtering local results through masking. While this tool is currently functioning as of today, it may not in the future.
The best methodology for tracking phrases as they are seen outside of your local area is to periodically check them through an anonymizer system, but not to worry about it unless you are targeting specific cities (probably due to physical locations in drive up areas.) If this is the case, geotargeting through use of a city in the search will also do the job. If you are simply seeking global results, track using an anonymizer at all times.
Your search engine optimization program should have been decided as global or local from the beginning anyway, unless there are special circumstances like a local business that also sells nationally through their website. In these types of cases, careful structuring of the SEO targets so as not to kill national rankings with local ones is going to be necessary. You also may want to split your programs across different websites, one local and one without local references. This way, your results are not swayed by a localization aspect and can be viewed by Google as more of a national business.