First, credit for this article goes largely to “The Finance Buff“, a great blog I just discovered today. He wrote a post about Employee Stock Purchase Plans (ESPP) that really struck a chord with me, and I thought I’d share it with my readers.

Employee Stock Purchase Plan (ESPP) Is A Fantastic Deal

Most people think of their ESPP plan as a nice little perk. But after running the numbers, it seems like it’s a much better return that people give it credit for. It’s definitely a much higher return, on average, than the 15% number that people tend to gravitate to.

Let’s walk through the highlights of why by walking through the original post. First, he defines the basics of what an ESPP plan is:

An ESPP typically works this way:

1. You contribute to the ESPP from 1% to 10% of your salary. The contribution is taken out from your paycheck. This is calculated on pre-tax salary but taken after tax (unlike 401k, no tax deduction on ESPP contributions).

2. At the end of a “purchase period,” usually every 6 months, the employer will purchase company stock for you using your contributions during the purchase period. You get a 15% discount on the purchase price. The employer takes the price of the company stock at the beginning of the purchase period and the price at the end of the purchase period, whichever is lower, and THEN gives you a 15% discount from that price.

3. You can sell the purchased stock right away or hold on to them longer for preferential tax treatment.

Your plan may work a little differently. Check with your employer for details.

OK, so that covers the basics. I have seen minor variations on the above, but nothing that eliminates the math that he is about to walk through:

The 15% discount is a big deal. It turns out to be a 90% annualized return or higher.

How so? Suppose the stock was $22 at the beginning of the purchase period and it went down to $20 at the end of the period 6 months later. Here’s what happens:

1. Because the stock went down, your purchase price will be 15% discount to the price at the end of the purchase period, which is $20 * 85% = $17/share.

2. Suppose you contributed $255 per paycheck twice a month. Over a 6-month period you contributed $255 * 12 = $3,060.

3. You will receive $3,060 / $17 = 180 shares. You sell 180 shares at $20/share and receive $20 * 180 = $3,600, earning a profit of $3,600 – $3,060 = $540.

Percentage-wise your return is $540 / $3,060 = 17.65%. But, because your $3,060 was contributed over a 6-month period, the first contribution was tied up for 6 months, and the last contribution was tied up for only a few days. On average your money is only tied up for 3 months. So, earning 17.65% risk free for tying up your money for 3 months is equivalent to earning (1 + 17.65%) ^ 4 – 1 = 91.6% a year.

90%+ a year return is fantastic, isn’t it? That’s when the employer’s stock went down. Had the stock gone up from $20 at the beginning of the purchase period to $22 at the end, your return will be even higher at 180%!

I think the reason people focus on the 15% is a classic example of why people, even very educated people, are not very good intuitively at dealing with money. 15% feels like the value of the ESPP program, because that is the “cash on cash return”, as we used to describe it in venture capital.

Let’s take the example of a hypothetical engineer, Joe, who makes $85,000 a year working for Big Tech, Inc. Joe is a saver, and as a result he puts 10% of his salary into his ESPP plan. Over the course of the period, the stock goes nowhere. Big Tech shares are always worth $50.

At the end of six months, Joe has contributed $4250 to his ESPP plan. They take the lower of the two stock prices, which are both $50, and set the price at 15% lower, $42.50 per share. (You can tell that I used to be a teacher… my numbers are suspiciously turning out to divide out evenly…)

$4250 buys 100 shares at $42.50 each. Since you got a 15% discount, people think that you got a 15% return.

Wrong. A 15% discount actually means you got a 17.65% return. (Read that line again). You have stock worth $5000. But you only paid $4250 for it, for a gain of $750. $750/$4250 = 17.65%.

This isn’t some sort of numbers trick – it’s actually just the difference between looking at what discount you got off full price (15%) versus the return on your money that you received (17.65%). Percentages going down are always more than percentages going back up. For example, if you got a 50% discount on a $1000 TV means you only have to pay $500. But if they raise the price from $500 to $1000, that’s a 100% increase.

So that’s the first gotcha. And 17.65% is nothing to sneeze at. That’s better than the historical average return of every easily accessible asset class I know of (I am excluding Private Equity & Venture Capital, since most people do not have access to them.)

The second gotcha is the fact that Joe didn’t just give them $4250 one day, wait six months, and then got $5000 back. He actually paid it in gradually, paycheck by paycheck. So, he didn’t get a 17.65% annual return.

Now, this is the place where I’ll get technical and explain that Joe didn’t get 17.65% return over 3 months either… that math is faulty. To calculate this correctly, you need to do a cash flow analysis where you evaluate the internal rate of return taking into account each paycheck that Joe made.

In fact, using the numbers provided in my example, I get an annualized return of 98.4% for Joe – and that’s for a stock that didn’t go up!

Salary: $85,000.00
ESPP: 10%
Paychecks/Year: 26

1/14/06 $(326.92)
1/28/06 $(326.92)
2/11/06 $(326.92)
2/25/06 $(326.92)
3/11/06 $(326.92)
3/25/06 $(326.92)
4/8/06 $(326.92)
4/22/06 $(326.92)
5/6/06 $(326.92)
5/20/06 $(326.92)
6/3/06 $(326.92)
6/17/06 $(326.92)
7/1/06 $(326.92)
7/1/06 $5,000.00

IRR 98.4%

So, I think the lesson here is pretty clear. The biggest problem with ESPP programs is that you can only contribute up to 10% of your salary to them, typically. Otherwise, it would make sense to take out almost any type of loan in order to participate. You’d easily be able to pay it back with interest.

However, be forewarned. All of this analysis assumes that you will sell your stock the day you get it. It also is a “pre-tax” return, since you own income taxes on the $750 gain the day your ESPP shares are purchased.

Disclaimer: I am not a financial professional, and every personal situation is different. This blog is personal opinion, not financial advice. You should thoroughly investigate and analyze any financial decision yourself before investing any money in any investment program.

Update (11/10/2007):  There has been some commentary that questions the IRR calculation for this example.  I’ve uploaded an Excel Spreadsheet for this example.  It shows that for this series of cash flows every 2 weeks (13 negative, 1 positive) that the IRR is 98.4%.  For this spreadsheet, I use the XIRR function, which is part of the Excel Analysis Toolpack Add-on, which handles IRR calculations for non-periodic cash flows.

From Excel Help:

XIRR returns the internal rate of return for a schedule of cash flows that is not necessarily periodic. To calculate the internal rate of return for a series of periodic cash flows, use the IRR function.