6. Since the place of business must be fixed, it also follows that a permanent establishment can be deemed to exist only if the place of business has a certain degree of permanency, i.e. if it is not of a purely temporary nature. A place of business may, however, constitute a permanent establishment even though it exists, in practice, only for a very short period of time because the nature of the business is such that it will only be carried on for that short period of time. It is sometimes difficult to determine whether this is the case. Whilst the practices followed by member countries have not been consistent in so far as time requirements are concerned, experience has shown that permanent establishments normally have not been considered to exist in situations where a business had been carried on in a country through a place of business that was maintained for less than six months (conversely, practice shows that there were many cases where a permanent establishment has been considered to exist where the place of business was maintained for a period longer than six months). One exception has been where the activities were of a recurrent nature; in such cases, each period of time during which the place is used needs to be considered in combination with the number of times during which that place is used (which may extend over a number of years). Another exception has been made where activities constituted a business that was carried on exclusively in that country; in this situation, the business may have short duration because of its nature but since it is wholly carried on in that country, its connection with that country is stronger. For ease of administration, countries may want to consider these practices when they address disagreements as to whether a particular place of business that exists only for a short period of time constitutes a permanent establishment.