Most of us are locked into contracts that only make it money-smart to buy a new one every two years.
While the annual number of assassination attempts has been increasing (currently around one every two years), there are a lot more countries (and thus more leaders) than there were in the early 20th century.
The RNIB says that children under 16 and adults over 60 should have an annual eye test and the rest of the population should have one every two years unless they have been advised otherwise.
If you're at high risk of certain eye diseases, such as glaucoma, get an eye exam every two to four years up to age 40, then every one to three years between 40 and 54, and finally every one to two years at age 55 and older.
We also asked about this broad proposal: Increase the Social Security retirement age by one month every two years after it reaches 67 under current law.
Typically one person in the United States is infected with swine flu every one to two years, although there have been 12 cases in the three-year period between December 2005 and January 2009.
Rating performance and subsequent payouts will be recalculated every one to two years.
High-profile cases come along every one or two years in Northern California.
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Mr. VOGEL: It's very hard to do even one hit picture a year, and some people would say even one hit picture every two years.
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Against the headwinds of the slowest recovery since 1960, small business owners are dealing with a tax system that is hopelessly complex, full of provisions that expire every one or two years, riddled with special exemptions, deductions and preferences and filled with new penalties.
We plan to release the first new Star Wars film in 2015, and then plan to release one film every two to three years.
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By law, states must inspect bridges like the one on I-35W every two years.
Every two years one-third of the Senate and all 435 seats in the House are up for grabs, giving voters a real chance to shape the political landscape.
Other interesting statistics from a recent Symantec study suggests that businesses are storing 2.2 Zettabytes of information and that data creation doubles every two years with one gigabyte of stored data creating a petabyte of transient data.
If asteroids as big as DA14 pass close to Earth once every decade or two, and meteors as large as the Chelyabinsk one impact once every 100 years (a similar meteor having caused the Tunguska event in 1908), the chance of both events happening on any one day are indeed very small: 1 in 3, 650 days times 1 in 36, 500 days, or about 1 in 100 million -- not odds you would bet against.
After a year, investors get one share for every 20 held, with a further one-for-15 bonus promised after two years.
Mrs Edwards now has to take one tablet of Thalidomide every night for the next two years.
The scheme involves nurses visiting expectant mothers every one or two weeks and throughout the first two years of their baby's life.
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That's why every two years, I will ask one million citizens to come together to tackle our toughest issues in local forums across the nation.
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Later, she also determine that batteries needed to be replaced every two years, and set up a database to automatically send letters to every customer one month before their battery expired creating a whole new revenue source for her business.
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In the last two years, they lent me every three months one newspaper that was one month old.
In contrast, China launches a mission about every two years, but takes large steps with each one and has a much longer timeline for achieving its goals.
Under the plan, each team must play the other nine Test sides in at least two Tests and three one-day internationals at home and away every six years.
This visa must be renewed every two years, but there is no limit to how many times one can renew.
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"It hasn't been real productive the last two years, and frankly every time I've gotten into one of these high-profile negotiations, it's my rear end that got burnt, " Boehner said.
Agents are required to sit an exam every five years to re-qualify, with licensed agent Rob Shield saying he was one of only two to pass out of more than 100 people when he took the test.
One of its long-term partners, Google, has a search deal with Mozilla that is renewed every two or three years.
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