The meaning spherical is an archaism, and the meaning worldwide a novelty; both should be avoided. The standard current meaning is "pertaining to or embracing the totality of a group of items, categories or the like". Thus the price paid by the State for the coal industry was arrived at by taking a "global" figure as the value of the industry as a whole, and not an "aggregate" figure of the values of the separate collieries. The word is enjoying a spell of popular favour; it is made too much of, and used in many senses which it will not bear. Do not use either it, or overall, as a showy substitute for total or aggregate.