Understanding GDP Chart When I Google "GDP of 1950", I get ~$300 Billion.

Looking at the graph @ https://fred.stlouisfed.org/series/GDP . I see


Q1 280 billion
Q2 290 billion
Q3 308 billion
Q4 319 billion


My questions:


Does last quarter value represents the GDP of the year? I thought we generally add all 4 quarters to get the annual number in finance?
Does GDP reset to 0 every year? So Jan 1st 12:00am, value starts at 0?
Is GDP culimnative? So the GDP created Q2 1950 is actually ~10 billion, and we just add that to the value of the previous quarter (to get ~290 billion)?
If the GDP value is culminative,  and you only add to the value of last quarter, the only reason why you can have a lower overall GDP is export is higher? The GDP equation is (GDP = C + I + G + (X – M)). The only subtraction I see in the equation is export. Or can  consumer spending, business investment, and goverment spending be negative???
What you are seeing in the data provided in the google search is an annual estimate  of GDP.  In the FRED data download is GDP reported on a quarterly basis.


Does last quarter value represents the GDP of the year? I thought we generally add all 4 quarters to get the annual number in finance?


Add up the all the quarters nominal estimates and divide the total by four to get the annualized numbers. (but when it reals you do not add them up, as real terms are not additive)


Is GDP culimnative? So the GDP created Q2 1950 is actually ~10 billion, and we just add that to the value of the previous quarter (to get ~290 billion)?


Nominal GDP estimate is the market value of the goods and services produced by labor and property located in the United States for that particular time period (quarter).  The estimate is not a running total from previous periods. 

Now if you are asking if the nation's economy grow or contract compared to the previous period measured?   Then the GDP growth rate tells you how fast a county's economy is growing. It compares real GDP from one quarter to the next.

new: 2. Does GDP reset to 0 every year? So Jan 1st 12:00am, value starts at 0?

It depends on the country.  In the US, the source data for GDP is collected every month and the GDP is estimated at every quarter  once all final estimates are collected for each quarter in the year then the annual estimate is published (note there are revisions to the data and on a quarterly basis revisions are published 3 times). 

https://www.bea.gov/resources/learning-center/what-to-know-gdp


If the GDP value is culminative, and you only add to the value of last quarter, the only reason why you can have a lower overall GDP is export is higher? The GDP equation is (GDP = C + I + G + (X – M)). The only subtraction I see in the equation is export. Or can consumer spending, business investment, and goverment spending be negative???


It would be really bad if GDP in nominal or real terms are negative.  However, GDP growth (percentage change)  can be negative but the interpretation is different as the growth rate tells you how fast a county's economy is growing.
The (X – M) term is defined as “net exports” .  So in the case where imports M is greater than exports X then net exports would be negative.      The other components would typically not have a negative values unless something catastrophic happens.