E:D Community Goals have global rewards given to all contributors, and also personal contribution tiers that determine what level of reward you get at the end of the challenge. Below, this post shows the different possible rewards based upon the percentage of players that have contributed as much as you have.
For instance, in the above screenshot, the Colonia Connection Goal is based around trade. I found that delivering 160 tons (my entire cargo hold) put me in the top 75%. Delivering 320 put me in the top 50%. I have now delivered 640 tons and I am still in the top 50%. Other than the raw sale of the goods I'm transporting (160 tons of Titanium nets 90k), these last two deliveries haven't made me any more money in terms of the challenge reward. It might keep me from falling below the 50% mark if other players start making bigger hauls, but perhaps I wasted my time and fuel and chaff (pirates surround these Community Goal locations).
Is there a way (in-game or 3rd party tool) to see the contribution levels for each tier? Even just seeing more fine grained detail about the challenge might allow me to calculate the tiers on my own, so any source that provides active challenge progress insight would probably be helpful.
Best Answer
Short Answer: No.
Frontier Developments has not provided any API or other public source of trade data, or any other in-universe intelligence, which goes substantially beyond what is visible in-game.
Even the source of your screenshot, INARA, is populated solely by volunteer players who are taking the data from their in-game displays.
There have been some efforts to perform analysis on Community Goal progression, so that the threshold for each tier can be estimated. (i.e.: The tier represented in the "PROGRESS" line of Community Goal entries on INARA) However, even these ultimately result in semi-educated guesses from unofficial sources.
As for your percentile rank for rewards distribution, I'm not aware of anything that can predict that placement - official or not. What's worse, this status is even more volatile (and therefore less predictable) than the Community Goal tiers. While you might manage to achieve the upper echelons one day, you never know when some ambitious individual or group might decide to raise the bar far beyond its present state.