text: (CNN)As the Great Kate Wait of 2015 drags on, giving a whole new meaning to Kate's somewhat unfair noughties nickname, "Waity Katie," bets on the arrival of a new baby a girl continue to be placed at a feverish rate. As of today, 70% of those laying down their hard earned cash are convinced the world is on the verge of welcoming a new princess. I suspect different parties are hoping for a girl for different reasons. Based on the so called "Kate Effect" and subsequent "George Effect," the great British High Street is no doubt salivating at the prospect of record sales should HRH Princess (fill in the blank) of Cambridge be spotted in one of their outfits. As one headline blared this week, "Baby girl could be worth $1.5 billion to the country." Magazine and newspaper editors are well aware of the dramatic rise in sales when a royal baby hits the cover, especially a little girl. And then there's Disney, which will always appreciate princesses in the zeitgeist, but as with all things relating to the monarchy, there is also a far greater historical significance should a baby girl arrive. There have been 34 Kings and only six Queens over the course of the British Monarchy's thousand-year history, and yet some of the nation's most enlightened times have occurred when a Queen has been on the throne. Elizabeth I led the country through the Golden Age, and Victoria and Elizabeth II -- the two longest reigning monarchs -- both made their mark with perhaps the most illustrious and progressive legacies of all. While it is unlikely this child will ever be crowned, as the daughter of the second-in-line to the throne, her role will be significant. Prince Charles has made no secret of his desire to slim down the monarchy, but in looking at his family's immediate bloodline -- William, Harry and George -- it stands to be a heavily male-dominated one. In an institution viewed by some as archaic and out of touch, it is imperative to have a strong female presence. Princess Anne -- Baby Cambridge's great-aunt -- grew up with three brothers, and was once described as, "the greatest King the country never had." She is patron of more than 200 charitable organizations and carries out some 500 public engagements a year. A noted equestrian, she won two silver medals and a gold at the European Eventing Championships, and was the first member of the royal family to compete at the Olympics. More importantly she has supported her mother throughout her reign, flown the flag for Britain and promoted brand Windsor around the world. As the only girl born to Elizabeth and Philip, she has matched and often surpassed the accomplishments of her brothers. Princesses Beatrice and Eugenie, also true blood princesses, are not "working members" of the royal family and generally only roll out for state and ceremonial occasions. So, yes, it would be nice for the baby to be a girl so that we can all ooh and ah over frilly dresses, fairy wings and ballet shoes (although as a Windsor she's more likely to be mucking out stables and shooting pheasant), but in truth the birth of a girl matters on a far deeper level: the monarchy needs a baby girl to fill the female void of future generations. The 20th century was ushered in by Queen Victoria and the 21st by Queen Elizabeth II. Should George live to eighty-seven he will be the first monarch of the 22nd century, but as I have said before the British monarchy is anything but predictable. If punters are right and William and Kate do announce the birth of a baby girl as the rightful "spare," it's certainly possible that a seventh Queen may ring in the year 2100. In the event the couple welcomes a boy, however, I sincerely hope there won't be a collective groan of disappointment heard around the world -- after all on the few occasions we have seen Prince George he has been a veritable treat. The birth of any baby is cause for celebration regardless of gender, race, religion or indeed status, and as Prince Harry, the world's most eligible bachelor has shown, games of naked billiards can sell magazines too. READ MORE: Please don't name the royal baby Diana .
target: British monarchy's 1,000-year history has seen 34 Kings and just 6 Queens on the throne .
  Victoria Arbiter argues the royal family needs a baby girl to fill the female void of future generations .