O.k., here we enter into the error of the "SOUNDEX"!  Our U.S. Federal Census records have increased dramatically along with the population.  There are so many people now that it made a lot of sense to instate a Soundex (Index of the U.S. Federal Census).

Here are the directions for how to calculate your "Soundex Code" for you last name.  It is a little tricky but you'll get the hang of it. 

Basic Soundex Coding Rule: (Thanks to GedPage for the info.) 
Every soundex code consists of a letter and three numbers, such as W-252. The letter is always the first letter of the surname. The numbers are assigned to the remaining letters of the surname according to the soundex guide shown below. Zeroes are added at the end if necessary to produce a four-character code. Additional letters are disregarded.
 
1) B,P,F,V
2) C,S,K,G,J,Q,X,Z
3) D,T
4) L
5) M,N
6) R

Examples:
Washington is coded W-252 (W, 2 for the S, 5 for the N, 2 for the G, remaining letters disregarded).
Lee is coded L-000 (L, 000 added). Additional Soundex Coding Rules

Names With Double Letters
If the surname has any double letters, they should be treated as one letter. For example:
Gutierrez is coded G-362 (G, 3 for the T, 6 for the first R, second R ignored, 2 for the Z).

Names with Letters Side-by-Side that have the Same Soundex Code Number
If the surname has different letters side-by-side that have the same number in the soundex coding guide, they should be treated as one letter. Examples:
Pfister is coded as P-236 (P, F ignored, 2 for the S, 3 for the T, 6 for the R).
Jackson is coded as J-250 (J, 2 for the C, K ignored, S ignored, 5 for the N, 0 added).
Tymczak is coded as T-522 (T, 5 for the M, 2 for the C, Z ignored, 2 for the K). Since the vowel "A" separates the Z and K, the K is coded.

Names with Prefixes
If a surname has a prefix, such as Van, Con, De, Di, La, or Le, code both with and without the prefix because the surname might be listed under either code. Note, however, that Mc and Mac are not considered prefixes.

For example, VanDeusen might be coded two ways:
V-532 (V, 5 for N, 3 for D, 2 for S)
or
D-250 (D, 2 for the S, 5 for the N, 0 added).

Consonant Separators
If a vowel (A, E, I, O, U) separates two consonants that have the same soundex code, the consonant to the right of the vowel is coded. Example:
Tymczak is coded as T-522 (T, 5 for the M, 2 for the C, Z ignored (see "Side-by-Side" rule above), 2 for the K). Since the vowel "A" separates the Z and K, the K is coded.
If "H" or "W" separate two consonants that have the same soundex code, the consonant to the right of the vowel is not coded. Example:
Ashcraft is coded A-261 (A, 2 for the S, C ignored, 6 for the R, 1 for the F). It is not coded A-226.

If this is way to hard for you to calculate on your own, like it is for most of us, you can go to a "Soundex Calculator" online at:

http://www.frontiernet.net/~rjacob/soundex.htm

The 1870 U.S. Federal Census has increased, again, the amount of questions asked.  The questions are becoming more specific and this is when male U.S. Citizenship became a question.

1)  Dwelling-houses numbered in the order of visitation.
2)  Families numbered in the order of visitation.
3)  The Name of every Person whose place of abode on the first day of June, 1870, was in this family.
Description:
4)  Age at last birth-day.  If  under 1 year, give months in fractions, thus 3/12.
5)  Sex – Male (M), Female (F).
6)  Color – White (W); Black (B); Mulatto (M); Chinese (C); Indian (I).
7)  Profession, Occupation, or Trade of each Male Person over 15 years of age.
Value of Real Estate:
8)  Value of Real Estate.
9)  Value of Personal Estate.
10) Place of Birth – Naming the State, Territory, or Country.
Parentage:
11) Father of Foreign born.
12) Mother of Foreign born.
13) If born within the year, state month (Jan, & c.).
14) If married within the year, state month (Jan, & c.).
15) Attended School within the year.
Education:
16) Cannot read.
17) Cannot write.
18) Whether deaf and dumb, blind, insane, idiotic, pauper, or convict.
Constitutional Relations:
19) Male Citizens of U.S. of 21 years of age and upwards.
20) Male Citizens of U.S. of 21 years of age and upwards where rights to vote is denied on other grounds than rebellion or other crime.

1860 Slave Schedules & 1860 U.S. Federal Census – Slave Schedules.  As you can see, this information didn't change much from the prior Slave Schedule.  Thank goodness this was the last slave schedule!  The Emancipation Proclamation was made during the Civil War in Sept. 1862 and took affect on January 1, 1863.  This took affect in the Confederate States.  Then, by 1865 all slaves were freed completely from all of the states in the union, including the Union States.   

1)  Names of Slave Owners.
2)  Number of Slaves.
Description:
3) Age
4)  Sex
5)  Colour
6)  Fugitive from the state.
7)  Number manumitted (To free from slavery or bondage; emancipate).
8)  Deaf & dumb, blind, insane, or idiotic.

1860 U.S. Federal Census information is about the same as the last decade.  The only thing that was added was the "Value of Personal Estate".  So, they wanted to get a better idea of the exact worth of people, not just their land worth.

1)  Dwelling-houses numbered in the order of visitation.
2)  Families numbered in the order of visitation.
3)  The Name of every Person whose usual place of abode on the first day of June, 1860, was in this family.
Description:
4)  Age
5)  Sex
6)  Color (White, black, or mulatto).
7)  Profession, Occupation, or Trade of each Male Person over 15 years of age.
8)  Value of Real Estate.
9)  Value of Personal Estate.
10) Place of Birth Naming the State, Territory, or Country.
11) Married within the year.
12) Attended School within the year.
13) Persons over 20 yr’s of age who cannot read & write.
14) Whether deaf and dumb, blind, insane, idiotic, pauper, or convict.

1850 was the first of two years that they did a U.S. Federal Slave Schedule.  This is the information that it included. 

This is such a blessing for black americans that want to trace their ancestors.  I've been able to help several of my friends by referring to this information! 

1)  Names of Slave Owners.
2)  Number of Slaves.
Description:
3)  Age
4)  Sex
5)  Colour
6)  Fugitive from the state.
7)  Number manumitted (to free from slavery or bondage; emancipate).
8)  Deaf & dumb, blind, insane, or idiotic.

In this U.S. Federal Census it looks like they standardized the form that was filled out.  The ledger now has blanks that are filled in and it seems to be more uniform.  This is a plus since some of the census records prior to this time, had a little bit of variance that can throw us off if we are looking at different state's records. 

Also, you'll notice that the amount of information had decreased this decade!  This is just another wave in the Census Ocean!