IS curve

  

Categories: Metrics, Econ

The IS curve is the “investment-savings” curve, and one of two main curves on the macroeconomic IS-LM model. The IS-LM model is part of Keynesian economics (in vogue).

The IS-LM model has two curves: one IS (investment-savings) and one LM (liquidity preference-money supply). The IS curve is downward sloping, like a demand curve on your typical supply and demand graph, and the LM curve is upward sloping, like the supply curve on a consumer S&D graph. The y-axis is “interest rate” and the x-axis is “investment.”

The IS curve descends because the higher the interest rate, the less firms will be investing. The farther you move down (and to the right) on the IS curve, the lower interest rates are, and the higher capital spending is for firms.

But the IS curve also represents something else...well, rather, everyone else (consumers and the government). Part of this macroeconomic theory is that the firm’s “I” is also the country’s “S,” which is consumer saving plus government saving (surplus only) plus foreign saving (trade surplus). Like firms, consumers and the government are incentivized to save more and spend less when interest rates are high. Since I = S, both of these are represented by the downward-sloping IS curve.

The IS-LM model is used by macroeconomists to analyze the big picture...like trying to explain changes in aggregate demand and national income. Yep, the really big picture, all in one graph.

Related or Semi-related Video

Econ: What is Income Distribution?2 Views

00:00

And finance Allah shmoop What is income distribution All right

00:08

What's income distribution Well it's income You know those paychecks

00:12

you get sometimes Yeah how it's distributed among the masses

00:16

in a country and or around the world But normally

00:19

the way we look ATT income distribution is to divide

00:22

a nation's population into five or ten equal groups And

00:26

then we can look at how much of the total

00:27

GDP pie each of those equal groups of people is

00:30

getting well When the pie slices are sliced equally that's

00:34

an equal distribution of income The more unequal the pie

00:38

slices look while the more unequal income distribution is those

00:42

are just the facts and what we'd call positive economic

00:45

statements But it's normal Have opinions When we're talking about

00:48

economics which are called normative statements many people think that

00:52

the more unequal income distribution is the less fair it

00:56

is Plus there's some economic theory and research backing the

00:59

idea that extreme income inequality can actually be bad for

01:03

the economy But well even that's up for debate It

01:06

depends how you define the economy Economist have come up

01:09

with a genius tool for making measuring income distribution as

01:12

easy as pie and well actually even better than a

01:15

pie chart It's called the Loren's Curve and the Gini

01:19

coefficient These things right here if a nation was perfectly

01:22

equal it would be a straight diagonal line like this

01:27

If you look at the X and Y axes well

01:29

this makes sense The X axis is the buckets of

01:31

people in the Y Axis is the percent of money

01:33

to be spread among them on a straight line The

01:35

bottom ten percent of people are getting well ten percent

01:38

of the money The bottom fifty percent of people are

01:40

getting fifty percent of the money in the bottom ninety

01:42

year getting ninety percent right The more saggy the line

01:45

is like there's the sags the less equal it is

01:47

Well for instance as income distribution has become less and

01:50

less equal in recent decades sort of depending on how

01:53

you do the math the US Lauren's curve has gotten

01:56

Sagheer and saggy er just like your skin will one

01:59

day Sadly trust us in this graph Using data from

02:02

the late nineties in early two thousand's you can compare

02:05

Denmark in Hungary two of the countries with some of

02:08

the most equitable income distribution with Namibia one of the

02:12

least equitable The first line below the blue one is

02:15

Denmark In the second between the yellow silver and red

02:18

area is Hungary and the third one that one's Namibia

02:22

See how saggy Namibia is Well if you look at

02:24

the bottom eighty percent of the people the four on

02:27

the X axis there you'LL see that they were only

02:29

getting twenty one point three percent of the nation's income

02:32

Now that you understand how Lauren's curves work either keeping

02:35

things tight or saggy there we're going to take a

02:37

look at the Gini coefficient Well the Gini Coefficient takes

02:40

the Lauren's curve reducing income distribution down to a single

02:44

number You know like a jet I take a look

02:47

at this graph The more sag there is to our

02:50

Lauren's curve while the bigger the area gets and the

02:53

smaller the B area gets the Gini coefficient is a

02:57

over a plus B If our Lauren's curve overlaps with

03:00

our perfectly equal straight line well then the area is

03:04

zero making our Gini coefficient also zero But what if

03:07

the saggy sag sags all the way down to the

03:10

X axis which means income is distributed really really unequally

03:15

Well that would make the Gini coefficient one right Gini

03:18

coefficients are ratios so they're always expressed as a number

03:21

between zero and one sometimes expressed as a decimal or

03:24

a percentage the closer to zero The more equal the

03:28

income distribution in the closer the one the less equal

03:31

Well the Gini Coefficient takes all those numbers the stilling

03:34

income distribution into one single number meaning that it's super

03:37

easy to compare income distribution of different countries Though it's

03:41

good to remember these air more estimates than actual numbers

03:43

Since most countries inflate or deflate their GDP numbers they're

03:47

international politicking and all the other crap that goes behind

03:51

it So just is the U S Lauren's curve has

03:53

been sagging as time goes by at least in the

03:56

modern era with income distribution getting less and less equal

03:59

It's Jeannie Cooper Fishing has been getting bigger and bigger

04:02

Okay so what's the role of taxes in income distribution

04:06

How do they work Well there are progressive taxes and

04:09

regressive taxes Progressive taxation is where you pay a higher

04:13

percentage in taxes The more money you make For instance

04:17

in the country of United Simpleton Sze Everyone pays ten

04:21

percent on their first twenty grand than twenty percent on

04:24

their next eighty and then fifty percent on any income

04:27

over one hundred grand Well these different buckets are called

04:30

tax brackets and under this quote progressive unquote tax system

04:34

Billy Bob who makes thirty grand a year's tax at

04:36

ten percent on his first twenty grand of income and

04:38

twenty percent on his last ten thousand of income That

04:41

leaves Billy Bob with twenty six grand to live on

04:44

Well then he have Joe Schmoe who makes one point

04:46

five million dollars Well he's taxed ten percent of his

04:48

first twenty grand twenty on his next eighty and fifty

04:51

percent on his remaining one point four million That leaves

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Joe Schmo with seven hundred eighty two thousand dollars to

04:56

live on A regressive tax also known as a flat

05:00

tax is where all income is taxed at the same

05:03

rate No matter how much you make it's called a

05:05

regressive tax since it takes a more meaningful percentage of

05:08

income from low income people compared to high income people

05:12

to pay those taxes For instance if the united simple

05:15

Don's had to pay twenty five percent on their income

05:17

Well that would leave Billy Bob with twenty two thousand

05:19

five hundred dollars and Joe Schmo with one million one

05:22

hundred twenty five thousand dollars Well because there are so

05:24

many normative opinions on what's fair when it comes the

05:26

income distribution there's plenty of debate over what level of

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taxation and social programs and public services are best to

05:32

use So yeah there's certainly plenty room for all this 00:05:34.933 --> [endTime] debate but on leave politics for another video Oh

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