A Lumen is basically the unit of measurement used in lighting to express the amount of light emitted by a bulb or a lamp. Formerly we understood that the more watts had a light bulb more "would", this currently with the LED has completely changed. Now we have to take into account the lumens for the amount of light and not the wattage, since a 8W LED bulb can give less light than a 6w. A bulb with more "power" has fewer lumens than a less depends mainly on the quality of LED employee and energy efficiency.
It is difficult to say equivalence LED bulb to incandescent or fluorescent and any comparison table is outdated in a few months. But whenever you bet on LED bulbs brands, the lumen / w ratio approaches the table below.