Managing Your Money - Building a Personal Financial Model

Inspired by: I cant save money

tl;dr: This could be the most important model you ever build.

Prologue

When I started IBD in Toronto, I had a mortgage but no house. My MBA student loan was pretty bad (Canadian schools, while they don't enjoy the prestige of our US counterparts, can nonetheless be equally expensive). The worst and probably most embarrassing part is, despite being a low cost of living location (globally speaking) and relatively high comp (all-in pay for Analysts and Associates is comparable to places like NYC), I was somehow not saving any money. I would need to blow off steam, usually aggressive drinks with the guys (lots of bottles, although not so much models. I know... no game). I think the point is if you are willing to spend money, there is always someone willing to take it.

I had a short but rough unemployment patch before starting my MBA and the idea of living with no income and eating into my savings was still too fresh in my mind. Yet, because of the stresses of banking, I couldn't help but want to blow off steam. Aggressively. One night after waking up to a bill of several k's, I decided that this was a bad strategy. Being a finance nerd, I figured the solution was to build my own personal financial model. I realized afterwards that some of my colleagues had them as well.

In the hopes of helping other monkeys avoid some of the stupid mistakes I have made, I would like to present the high level steps for how I build a personal financial model and how it helped me get a handle on my spending. To be clear, the model didn't change my day-to-day spending (I didn't stop going out for lunch, drinks or buying my friends and family gifts etc.), but it just made it clear where all my money was going so I felt more comfortable with my habits.

It's actually gotten to the point where I was speaking to a financial advisor recently and they said I might be saving too aggressively (sure, he was trying to sell me his investment products, but I'll take the compliment).

1. Top-Line

Easiest step. How much do you make on your regular pay check? The only trick is that taxes change throughout the year as you pay off your Social Security (Canadians: Social Insurance) over the year, but otherwise this part should be pretty predictable.

The trickiest part is bonus, but I think most people will tell you to "bank your bonus" so I didn't even model it in my first few years. And what ever I got made sure I hit my $18k 401k max (or RRSP for Canadians) first and the rest was to pay down student debt / save.

2. Budgeted Expenses

This is the trickiest part. It's often hard to estimate your expenses. I had two categories: run-rate (monthly) budget (rent, dinners, lunches, coffees, occasional drinks, transportation etc.) and discrete seasonal (planned holidays, birthdays, gifts, charitable donations etc.).

I created what I thought was a typical budget. And then to back check, I downloaded the last three months worth of credit card statements, categorized all the expenses and compared my budget to my actual spending. I was actually pretty close, but had to make some adjustments (ate out a little more than I expected and the meals after tax and tip were a little higher than I originally thought).

Also, once you get to this step, you can start to calculate how much you should be saving on a regular basis. After this step, I set up an automated transfer from my checking to savings (or initially, student debt pay down). I also calculated my own min-cash balance as I wanted to pay down my debt as fast as possible.

3. "Unique One-Time Adjustments"

This is the most important part. Tracking unbudgeted overspend. Once you have parts 1 and 2, you need a place to track your actual spending against your anticipated spending. Any large deltas have to be captured and a comment put in place. This won't immediately change your spending habits, but as you see it over time, you become more aware of where you are wasting money.

If I overspent, I knew I wouldn't be able to make my automated saving target and would either have to cancel it, or temporarily transfer money from my savings to checking. That forced me to acknowledge that I had mis-calculated: something I did not enjoy on a very visceral level. Missing targets then became very obvious.

4. Retirement - LTIP

Make a LTIP for yourself. I found that this helped. Because what's the point of making a short term goal if there isn't a long term objective? This is highly illustrative math for myself, but I like to think that with reasonable assumptions, I'm doing ok in the long run also. Getting a financial advisor at this point also helps (and I can keep them honest because I can back check their work against my personal model).

Epilogue

I built my personal financial model several years ago now. I paid off all my student debt within two years (not hard to do in IBD if you aren't stupid about spending) and have saved a decent amount of money. I deliberately dragged paying my student debt towards the end. I deliberately kept a small balance to encourage myself to stay hungry and as a reminder of leaner times. Also, it was cheap capital. I also have several years of records and can tell you exactly how much I've spent over the years. I haven't enjoyed life any less, but I feel much more comfortable about my spending habits.

How about you? Do you have a personal financial model? Do you keep pretty close to it? Any other suggestions or tips for fellow monkeys? As always, SB's for helpful insight.

216 Comments
 
Best Response

bravo bro, bravo. I'm certainly a fan of budgets, and I do a lot of financial planning for clients, so I've been through these types of exercises. I think it'd be helpful if I shared some tips I use myself and have helped make my clients rich. remember, I have virtually no clients who are business owners or inheritors, they're all self made employees who worked their way up, mostly millionaires by early 40s.

  1. don't take one step forward & 2 steps back. I see it all the time where people load up on fixed expenses and then wait for bonuses + a 10% 401k contribution to bail them out. live below your means and you'll be able to save more (saving high % of your income is what leads to greater wealth). this may mean getting roommates, living in hoboken, not owning a car, but it doesn't mean no fun. mortgage/rent is usually the biggest culprit here, so keep living expenses manageable. the rule of thumb I'll use is 1.5%. if your monthly mortgage/rent is 1.5% of your pretax annual income, you're doing great. personally, mine is 1% but I live in a tier 2 city and my fiance works so I have more options than single new yorkers, but this has greatly freed up cash flow.

  2. make it automatic. even if you're a hedge fund analyst and are great at picking names, have something automatic that you put 100, 200, 500, 1000, whatever a month into that invests for you. in your 20s and 30s, time, not timing, is what matters. I don't care where you invest (FA, wealthfront, Vanguard, whatever), just dollar cost average every single month.

  3. don't treat a rise in income as a rise in lifestyle. of clients, this is the absolutely most critical. most of my clients get stock grants and big bonuses, they don't treat this as an opportunity to buy a ferrari or a new big house. sure, if they get a $100k bonus after tax, they may take 30k and do whatever with it, but they save the vast majority of all of that stuff. on raises, they don't take this as the impetus to join an expensive country club, change who they are, etc., they treat it as gravy. if you don't increase your lifestyle as your income increases, you'll be able to save more, which is the key here.

  4. they focus on work, not their finances. obviously I'm biased because this is what I do, but I think part of my clients' financial success has to do with their desire to invest their time & energy in bettering themselves at their career, rather than meddling with the most optimal savings strategy, trying to save a nickel here or a percentage point there. if your income is rising because you do well at your work and you can continuously save more as a result, the details and mechanics of your finances don't really matter.

I want to expand on this last point more, because this forum is naturally populated with detail oriented, analytical types who are all in finance. you all want to make the best investment decisions, earn the highest rate of return, and usually prefer doing nothing over risking making a sub optimal decision. I'm here to tell you you're WRONG. yes, it's important to get a feel for markets, but don't do it with all or even most of your money. yes, it's important to understand what to do, but don't overcomplicate things with macros for your monthly budget, doing modelling of future returns, sensitivity analysis on different savings strategies, just keep it simple. as I said in another thread: buy VT, add as much as you possibly can monthly & from bonuses, and go to the beach (and don't forget to thank me in 30 years).

sure, the election may create volatility this month, but you should still buy. sure, seasonality may affect markets in February as the new POTUS is inaugurated and we're disappointed by Q4 earnings with the backdrop of higher rates, but you should still buy. I've seen this with my friends and with some potential clients, they have analysis paralysis. just save money, as much as you possibly can. you can try to outperform or you can just accept market performance, but what's ruined most financial plans is not whether you were in index funds versus value funds versus DFA, it's not putting enough money away or it's being in cash at the wrong time. absolutely keep a cash cushion for emergencies or once your net worth starts to rise, but again, in your 20s and 30s, time not timing is what matters, so just continue to contribute and get back to work.

 

After a rough experience in one of my posts, I foresee shit coming my way once again but I don't care.

I fully and wholeheartedly endorse the idea that achieving colossal wealth is ONLY a matter of making more, not of spending less. The "save every penny" mentality is useless, if not detrimental. If you succeed after a long career in finance, whatever you save in an Economist subscription or a MacBook is financially irrelevant to your final net worth, especially considering how back-loaded your cash flow profile looks like in this business.

Living up to this pinchfist philosophy and taking it too seriously has the power to lower the probability of bumping across your MD while he's wearing your team's jersey in that upscale mall (and as a consequence, of starting a great promotion-accelerating chat) or having $20 craft limited-edition beers with that distant friend-of-friend that may put a word for you for some big name PE interview. If you want to be one of them, live and spend like one of them as far as possible, and don't charge it as COGS, book it as social capex. If you're out of luck, you may need to write that ingangible off one day, but fuck it, life's a bitch sometimes.

Well, and the fun part is that if you save and fail, in 30 years those $40 will have accrued to $91 at the 30y T-Bond rate (more likely $50ish once you remove inflation - thank Uncle Bernanke). That will buy you maybe a week longer before you hit the shelter at 30th and 1st Ave. Don't get me wrong, as a rational utility maximizer, I will always evaluate owning $X+e as better than $X, no matter how small "e" is. It is just that, from experience, such savings are seldom worth the time you need to invest to get them, and even when they prove to be, it's always ex-post, you really never know beforehand.

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