Jim Palmer, who is not a Libertarian Party official, but who is very interested in data about the Libertarian Party, has created a dozen clear interesting graphs showing how the party has done over the past decades. See them here.
They cover the number of donors to the national party, the revenue to the national party, past ballot access, the percentage of U.S. voters who voted for a Libertarian, the number of members who signed the party membership pledge, voter registration data, and the number of candidates.
After looking at the opening chart, scroll down to see the next chart. Ignore the button that says “next post”.