Do you really mean least efficient?
That looks like really horrible design, unless you are inserting those data into a database. Create a class which encapsulates those 5 data. You can work out the sizes of the two primitives easily enough. Strings vary depending on their size. Add a few dozen bytes to create the objects and multiply by 1000.
Which is a waste of time, because even the smallest modern computer will have enough RAM to fit 1000000 objects like that it.
By the way: there is a way to make such tables show up nicely: code tags