(Adds details on smuggling, companies, further links)
By Alexandra Ulmer and Girish Gupta
CARACAS, Feb 18 (Reuters) - Venezuela's central bank on Thursday released long-awaited data showing the depth of the OPEC country's recession, a day after President Nicolas Maduro announced a package of measures seen as insufficient to salvage the unraveling economy.
The bank reported that Venezuelan inflation hit 180.9 percent in 2015, one of the highest rates in the world, while the economy contracted 5.7 percent.
The data showed the depth of Venezuela's crisis and raised the prospect new measures may hurt Venezuelans without significantly improving finances in a country already facing shortages of basics like milk and medicines.
Under Maduro's emergency measures, the price of Venezuela's fuel - the world's cheapest - will be increased for the first time in nearly 20 years and the complex system of fixed exchange rates has been devalued and revamped.
The fuel increase could amount to 5 percent of this year's budget, according to Reuters calculations, and will give state oil producer PDVSA's strained balance sheets a breather.
However, it remains unclear if what Maduro announced as a "floating" exchange rate would actually be allowed to float, or like previous such rates effectively become fixed and fail to satiate demand for greenbacks, further weakening the bolivar on the black market.
"Cheap fuel was the only benefit we had left," said Angel Pina, 41, at a gas station in Caracas. "The increase should have happened a long time ago, but now we don't know what consequences it could have."
Filling a small car will still cost at most half the price of a soft drink, or around 20 cents at the black market rate. But coupled with the currency change it could fan price increases and hit already strained pocketbooks.
"The devaluation will temporarily exacerbate inflation, thus contributing to rising discontent, while goods scarcity will worsen on the back of lower oil prices," said Risa Grais-Targow at consultancy Eurasia.
The increase is also insufficient to stem lucrative gasoline smuggling to neighboring Colombia and Guyana.
"The measures will provide some fiscal breathing room for PDVSA but are insufficient to reduce demand for imports or gasoline, failing to improve the government's supply of foreign exchange or prevent a default later this year," said Grais-Targow.
Wall Street investors are increasingly concerned about a potential default, with Venezuela facing some $10 billion in debt payments amid a major cash crunch.
The devaluation will not significantly impact the remaining U.S. companies operating in Venezuela. Many decided long ago that the stronger exchange rates do not reflect reality and moved their accounts to weaker rates - writing off billions of dollars.
American Airlines, for instance, wrote off more than half a billion dollars in revenue last month.
The change in fuel prices, however, will provide some relief to state-owned PDVSA, which is facing major debt payments this year amid low oil prices.
The company said in a statement that if consumption patterns remain the same as last year, some 68 billion bolivars - equivalent to $6.8 billion at the strongest official rate but just $68 million on the black market - will be saved.
Venezuela's 91 octane gasoline will rise 1,329 percent to 1 bolivar per liter and 95 octane gasoline will rise 6,086 percent to 6 bolivars. Small queues formed in front of some service stations as drivers filled up before the measure kicks in on Friday.
The shift may encourage some drivers to load up on the cheaper 91 fuel - though that would likely hurt foreign firms who have been supplying Venezuela with specialized products for its domestically-produced gasoline.
As the economy has deteriorated, Venezuela's central bank has kept negative economic data under wraps, only publishing figures for 2015 last month.
In addition to the full-year figures, the bank said month-on-month inflation was 11.4 percent, 11.1 percent, and 8.7 percent in October, November and December of last year, respectively.
Critics say the inflation figures are severe low-balls as they exclude transactions made on the black market, where scarce products sell for tens if not hundreds of times their official price.
Following the data release, Spanish mobile phone provider Movistar said price-fixed services were out of sync with inflationary reality, warning that this disconnect made investments "unviable."
"An average monthly Movistar plan costs 476 bolivars. Much less than a kilo of ham," the company said in a statement.
Caracas' annual inflation figure for last year was 159.7 percent. However, outside the capital, where queues are usually longer and scarcity worse, the figure was much higher, reaching 224 percent in the central city of Barquisimeto, for example.
The International Monetary Fund estimates Venezuela's annual inflation will jump to 720 percent this year. Economists are predicting another harsh economic contraction.
"Maduro's measures won't solve this crisis, it's too late," said Maria Hernandez, 45, as she stood in line at a supermarket.
"Today, for instance, the queue is longer than it was yesterday." (Additional reporting by Corina Pons, Eyanir Chinea and Diego Ore in Caracas; Mircely Guanipa in Punto Fijo; Marianna Parraga in Houston; Editing by Chris Reese and Andrew Hay)