Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Districts | UBIGEO | Area\n(km²) | Population | Population density\n(/km²) | Created | Postal\ncode |
| --- | --- | --- | --- | --- | --- | --- |
| Ancón | 150102 | 299.22 | 29,419 | 98.3 | 29 October 1874 | 02 |
| Ate | 150103 | 77.72 | 419,663 | 5,399.7 | 2 January 1857 | 03 |
| Barranco | 150104 | 3.33 | 45,922 | 13,790.4 | 26 October 1874 | 04 |
| Breña | 150105 | 3.22 | 94,808 | 29,443.5 | 15 July 1949 | 05 |
| Carabayllo | 150106 | 346.88 | 188,764 | 544.2 | 4 August 1821 | 06 |
| Chaclacayo | 150107 | 39.5 | 39,686 | 1,004.7 | 24 April 1940 | 08 |
| Chorrillos | 150108 | 38.94 | 262,595 | 6,743.6 | 2 January 1857 | 09 |
| Cieneguilla | 150109 | 240.33 | 15,784 | 65.7 | 3 March 1970 | 40 |
| Comas | 150110 | 48.75 | 464,745 | 9,533.2 | 12 December 1961 | 07 |
| El Agustino | 150111 | 12.54 | 165,425 | 13,191.8 | 6 January 1965 | 10 |
| Independencia | 150112 | 14.56 | 197,308 | 13,551.4 | 16 March 1964 | 28 |
| Jesús María | 150113 | 4.57 | 58,588 | 12,820.1 | 13 December 1963 | 11 |
| La Molina | 150114 | 65.75 | 124,468 | 1,893.0 | 6 February 1962 | 12 |
| La Victoria | 150115 | 8.74 | 190,218 | 21,764.1 | 16 August 1921 | 13 |
| Lima | 150101 | 21.88 | 278,804 | 13,187.2 | 2 January 1857 | 01 |
| Lince | 150116 | 3.03 | 52,123 | 17,202.3 | 20 May 1936 | 14 |
| Los Olivos | 150117 | 18.25 | 286,549 | 15,701.3 | 7 April 1989 | 39 |
| Lurigancho | 150118 | 236.47 | 90,594 | 383.1 | 2 January 1857 | 15 |
| Lurín | 150119 | 181.12 | 55,953 | 308.9 | 2 January 1857 | 16 |
| Magdalena del Mar | 150120 | 3.61 | 48,445 | 13,419.7 | 10 May 1920 | 17 |
| Miraflores | 150122 | 9.62 | 92,815 | 9,648.1 | 2 January 1857 | 18 |
| Pachacamac | 150123 | 160.23 | 54,763 | 341.8 | 2 January 1857 | 19 |
| Pucusana | 150124 | 37.83 | 9,231 | 244.0 | 22 January 1943 | 20 |
| Pueblo Libre | 150121 | 4.38 | 71,892 | 16,413.7 | 2 January 1857 | 21 |
| Puente Piedra | 150125 | 71.18 | 203,473 | 2,858.6 | 14 February 1927 | 22 |
| Punta Hermosa | 150126 | 119.5 | 4,676 | 39.1 | 7 April 1954 | 24 |
| Punta Negra | 150127 | 130.5 | 4,473 | 34.3 | 7 April 1954 | 23 |
| Rímac | 150128 | 11.87 | 175,793 | 14,809.9 | 16 August 1921 | 25 |
| San Bartolo | 150129 | 45.01 | 5,733 | 127.4 | 5 May 1946 | 26 |
| San Borja | 150130 | 9.96 | 102,762 | 10,317.5 | 1 June 1983 | 41 |
| San Isidro | 150131 | 11.1 | 55,309 | 6,165.6 | 24 April 1931 | 27 |
| San Juan de Lurigancho | 150132 | 131.25 | 812,656 | 6,191.7 | 13 January 1967 | 36 |
| San Juan de Miraflores | 150133 | 23.98 | 335,237 | 13,979.9 | 12 January 1965 | 29 |
| San Luis | 150134 | 3.49 | 46,258 | 13,254.4 | 30 May 1968 | 30 |
| San Martín de Porres | 150135 | 36.91 | 525,155 | 14,228.0 | 22 May 1950 | 31 |
| San Miguel | 150136 | 10.72 | 124,904 | 11,651.5 | 10 May 1920 | 32 |
| Santa Anita | 150137 | 10.69 | 160,777 | 15,039.9 | 26 October 1989 | 43 |
| Santa María del Mar District | 150138 | 9.81 | 88 | 9.0 | 16 January 1962 | 37 |
| Santa Rosa | 150139 | 21.5 | 9,379 | 436.2 | 7 February 1962 | 38 |
| Santiago de Surco | 150140 | 34.75 | 272,690 | 7,847.2 | 16 December 1929 | 33 |
| Surquillo | 150141 | 3.46 | 84,202 | 24,335.8 | 15 July 1949 | 34 |
| Villa El Salvador | 150142 | 35.46 | 367,436 | 10,362.0 | 1 June 1983 | 42 |
| Villa María del Triunfo | 150143 | 70.57 | 355,761 | 5,041.2 | 28 December 1961 | 35 |
Question:
how many districts have a population density of at lest 1000.0?
Answer:
31