How many animal species have become extinct in the past year?

Scientists have identified and catalogued around 1,500,000 to 2,000,000 species (of animals and plants), most of which are insects (most of which are beetles). However, those are only the species that have been identified and described, many, many, many more exist - some scientists think there are 10 million (10,000,000) species on Earth, and others think there are 100 million (100,000,000) species on Earth! Biodiversity (the number of living organisms on Earth) is an incredibly hard thing to count. There are places on the Earth that have hardly been explored at all where diversity (the numbers of species) is extremely high, places like the tropical rain forest. The really scary thing is that, mostly as a result of the activity of human beings (pollution and destruction of the environment), lots of these species are going extinct before we even get a chance to identify them in the first place