That's one potential headline that could be derived from playing around with The Observatory of Economic Complexity, a web-based visualization app that is co-hosted and developed by Harvard and MIT, holding trade data for most countries. Liberia, along with most of the world's countries, has data on imports and exports available for years 1995-2010. It's fun to play around with and it's macro-economically enlightening.
Rubber should be unsurprising, and although Liberia has no shipbuilding industry above Fanti fishing boats, it does continue to offer one of the world's favored flags of convenience with the Liberia Ship Registry, which I've mentioned before.
Just based on legibility of text size as an indication of significant exports, its curious and fascinating that Liberia's exports were by and large just three classifications: Cruise Ships (31%) Rubber 30%, Petroleum (26%). As Liberia is and has always been an importer of fuel, the third category is a bit strange.
Diamonds, Cocoa Beans and Scrap Iron are the only other categories that can even be seen without zooming in, the latter not exactly being a growth industry. Raw iron ore should have significantly displaced these other categories the next year with ArcelorMittal's resumption of ore exports.