99% of people would do x

Solution 1:

The OP asked: I am wondering, does this figure of speech have no currency in the Americas?

The cliché “99 percent of + noun/noun phrase" is also used in the US.

From a self-help book entitled: I Will Teach You To Be Rich

Avoid those credit card offers you receive in the mail. [...] Out of every thousand students who are mailed offers, 150 accept them, an astonishingly high number. [...] Let's get real. Taking a credit card offer you get in the mail is like marrying the first person who touches your arm—99 percent of the time it's the easy decision, not the right one. Most people know better and go out and find what's best for them; they don't just settle for the horrible offers that fall in their lap

Later in the book, the author Ramit Sethi, shares this citation

I believe that 98 or 99 percent—maybe more than 99 percent—of people who invest should extensively diversify and not trade. That leads them to [a tracker] fund with very low costs.

Warren Buffett

In neither of the cited examples is the expression 99 percent (99%) meant to be taken literally. It is only a generalization, not a real statistic.

Musings

There are cases of course when the figure "99%" is used in its most literal sense, suggesting that the remnant 1% is both paltry and negligible. We hear of detergents and hand sanitizers killing 99.9 percent of all known germs and bacteria. But is citing "99 % of X" always a legitimate claim if it is backed up by hard data such as a study or a survey? Aren't many of these 99% of X claims spurious, facile, or just PR stunts? Consider the following:

1. "In fact, the latest information that we have shows that in recent years, over 99 percent of all new income generated in the economy has gone to the top 1 percent."

Sen. Bernie Sanders, April 19th, 2015

2. “Well, I guess if you look at the population of the countries that are represented in this particular agreement with Iran, the vast majority–the 99 percent of the world, is on the side of the United States and international partners in implementing this agreement."

White House Press Secretary Josh Earnest, Jul 19, 2015

3. In one of two new ads released Thursday, Apple shows an array of happiness that has rarely been seen—even in Apple ads. […] The voice declares that 99 percent of people who own an iPhone love their iPhone.

Chris Matyszczyk, contributor to CNET, July 10, 2015

Do all Americans believe 99% of iPhone owners love their phones? Do they believe that 99% of the world support American's foreign policy? Reality suggests otherwise. My hunch is that the vast majority of Americans recognize a rhetorical claim when they see one.

Solution 2:

The problem is that "99% of x" does have currency with Americans. When used hyperbolically (not literally) you are counterfeiting that currency.

The easiest way to lose an argument is to overstate your case. By using a false statistic, rather than a much fuzzier expression like "vast majority", you make it easy for critics to take cheap pot shots at your argument.

Rather than this being merely about your critics being pedantically literal, be aware that there is an entire educated community of scientifically minded Americans who object when scientific disciplines such as statistics are abused for the sake of argument.

I'm sure that 99% of Americans would agree with me =)

EDIT:

To be clear, I'm not claiming that Americans do not use the expression (heck I just used it). I'm claiming that using the expression without hard data to back you up is problematic. In certain cases such expressions, used without hard data, are actually illegal.

Scientists are constantly put in a quandary by this practice because they need simple expressions to convey ideas that have the weight of hard data behind them. When such expressions are co-opted by those who do not have hard data it diminishes both the expression and science itself.

I'm 99% sure that the Americans who disagree with me work in advertizing.

EDIT2:

Come to think on it, a great many scientific advancements come from the British people: radar, computers, and television to name a very few. I can only assume that, unlike us Americans, the educated scientifically minded British people haven't corrected you simply because they are too polite to do so.

99% of Brits probably think I'm pandering to them at this point but as long as they keep making Dr. Who I'm happy.

Solution 3:

We use "99%", in the states, but probably not as "99% of people," - more like:

"99% of the time, that would've worked."

-or-

"99% of the time, she's the last to leave the party." (US)

Solution 4:

I think this depends a lot on context and phrasing: Does it sound like you are engaging in poetic exaggeration, or does it sound like you are claiming a literal number.

Like someone said in the comments, if you were chatting about the difficulty of getting up in the morning, and you said, "When the alarm goes off, 99% of the time I just turn it off and go back to sleep", I don't think anyone would understand this to be a literal number. I've said things like that and heard others say things like that many times. If someone really challenged you to back up this statistic with documentation, I think most others in the conversation would think this person a little crazy.

On the other hand, if you were discussing politics and someone said, "This country should pursue policy X", and you replied, "But 99% of the people are against X", the other person might well interpret that as an attempt at a literal number and challenge it.

I'm sure there are cases where you could make a statement intended to be poetic exaggeration, and someone else could misinterpret it as a literal number.

Solution 5:

As an American, I hear "99%" all the time. The usual case is when a speaker would like to say "everybody does X," but is aware that such a statement is easy to refute with a single example. By assigning a percentage to it, the speaker admits that there will be some cases where the declaration does not fit, where you can find someone who doesn't do X.

Usually the pattern involves 9's, and the more 9's the more confident the speaker is that exceptions are outliers: 90%, 99%, 99.9%, 99.99%, all the way out to 99.9999%, which is "six-sigma" in statistical speech, and has become a favorite number for process engineering. I've also heard 95%, and I've also heard 98%, which as best as I can tell is "I'd say 99%, but I'm not quite that confident."