Since conference and of the Food and Agriculture Organization's publication World Festival of Trees, and a resolution of the United Nations in 1954: " The Conference, recognising the need of arousing mass consciousness of the aesthetic, physical and economic value of trees, recommends a World Festival of Trees to be celebrated annually in each member country on a date suited to local conditions "; it has been adopted by the Netherlands.

Since 1977, New Zealand has celebrated Arbor Day on June 5, which is also World Environment Day, prior to then Arbor Day, in New Zealand, was celebrated on August 4 – which is rather late in the year for tree planting in New Zealand hence the date change.

Since the focus of his book was calculation, Bede gave instructions for computing the date of Easter and the related time of the Easter Full Moon, for calculating the motion of the Sun and Moon through the zodiac, and for many other calculations related to the calendar.

Since April 2007, The Beano has had five revamps to help it keep up to date.

Since 1582, when the Catholic Church adopted the Gregorian calendar while the Eastern Orthodox and most Oriental Orthodox Churches retained the Julian calendar, the date on which Easter is celebrated has again differed.

Since the ecclesiastical new moon falls on a date from 8 March to 5 April inclusive, the paschal full moon ( the 14th of that lunar month ) must fall on a date from 21 March to 18 April inclusive.

Since there are two different calendars currently in use among various Orthodox churches, two dates are listed: the first date is the date on the traditional Julian Calendar, the second date, after the slash, is the same day on the modern Gregorian Calendar:

Since then the university has observed this date in its calendar as Convocation Day.

Since gravitational effects are all around us, it is impossible to pin down the exact date when humans first discovered gravitational mass.

Since a paper describing the algorithm had been published in August 1977, prior to the December 1977 filing date of the patent application, regulations in much of the rest of the world precluded patents elsewhere and only the US patent was granted.

Since this date, the Undertones have performed several tours across the UK, Ireland, Continental Europe and North America.

Since the first term of the original federal officials began on this date and ended 2, 4, or 6 years later, this became the date on which new federal officials took office in subsequent years.

Since these events recur at different intervals, this particular sequence should be unique: the doctors found only one occurrence of this sequence while searching between 1250 and 1115 BC, the 135-year spread around the putative date for the fall of Troy.

Since the date of Easter is calculated differently in the East and West ( see Easter controversy ), in most years the two traditions celebrate Pentecost on different days ( though in some years the celebrations will coincide, as in 2010 and 2011 ).

Since he was a younger son, little attention was paid to him during his youth and his date of birth is therefore unknown.

Since Vaceti is another name for the Vascones, this reference is evidence of Basque ( Gascon ) settlement or control of the islands by that date.

Since he didn't become consul, he most likely died before that date.

Since the date of his birth had never been recorded, he celebrated this day as his " Roman birthday " for the rest of his life.

Since that date there has been no further suggestion of banning the Australian flag from Big Day Out events.

Since the compilation of the Book of Joshua is regarded by textual scholars as late, probably being due to the deuteronomist, it is possible that the tribal allocations given within it date from after this annexation rather than before.

Since Mrs. Calhoun remembered only that the marriage had been in the spring, he started to plod through several months.

Since then commercial interest in mouthwashes has been intense and several newer products claim effectiveness in reducing the build-up in dental plaque and the associated severity of gingivitis ( inflammation of the gums ), in addition to fighting bad breath.

Since 1991, several thousand students from 21 countries have come to Achill to study and participate in ongoing excavations.

Since its disappearance from the Biblical narrative, there have been a number of claims of having discovered or of having possession of the Ark, and several possible places have been suggested for its location.

Since then, with several relaunches, an increase in funding and resources from the BBC and improvements in digital television technology, the channel has been able to diversify content, with two minute looped bulletins available to view via BBC Red Button, BBC News Online and the BBC's mobile website, alongside individual weather and sport bulletins.

Since 1916, there have been several different nutrition guidelines issued by the United States government, eventually leading up to the food pyramid.

Since several elements are gases at commonly encountered temperatures, their densities are usually stated for their gaseous forms ; when liquefied or solidified, the gaseous elements have densities similar to those of the other elements.

Since its construction, the tunnel has faced several problems.

Since its arrival in 1974, what is known as Danza Azteca in the U. S., ( and known by several names in its homeland of the central States of Mexico: danza Conchera, De la Conquista, Chichimeca, and so on.

Since Chinese traditional thought focuses more on ethics rather than metaphysics, it has developed several schools distinct from the originating Indian schools.

Since 1987, the CRTC has been involved in several controversial decisions:

Since Engelbart introduced the keyset, several different designs have been developed based on similar concepts.

Since these first accounts, Bulgarian authorities had organized several population censuses: 1892, 1900, 1905, 1910, 1920, 1926, 1934, 1946, 1956, 1965, 1975, 1985, 1992, 2001 and 2011.

Since the 1990s, several novel classes of antiemetics have been developed and commercialized, becoming a nearly universal standard in chemotherapy regimens, and helping to successfully manage these symptoms in a large portion of patients.

Since then several beta keys have been handed out to those who have completed an online survey.

Since then the standard has been enhanced several times with added features.

Since his university retirement Husserl had " worked at a tremendous pace, producing several major works.

Since life began on Earth, several major mass extinctions have significantly exceeded the background extinction rate.

Since then, there have been several issues of agreement as well as of dispute.

Since Everquest's release, Sony Online Entertainment has added several EverQuest-related games.

Since the 1980s, several cities have re-introduced it.

Since the turn of the 21st century, several additional professionals are now routinely listed in the production credits on most major motion pictures.

Since they are based on several independent sets of measurements taken decades apart by different observers with different instruments, systematic errors may have influenced them.

" Since these tablets predate the Sulbasutras period by several centuries, taking into account the contextual appearance of some of the triples, it is reasonable to expect that similar understanding would have been there in India.

Since 1994, Lineker has featured in several television commercials for Walkers Crisps.